diff --git a/daffodil-core/src/main/scala/org/apache/daffodil/core/runtime1/TermRuntime1Mixin.scala b/daffodil-core/src/main/scala/org/apache/daffodil/core/runtime1/TermRuntime1Mixin.scala
index 418a50ceed..2d25012c74 100644
--- a/daffodil-core/src/main/scala/org/apache/daffodil/core/runtime1/TermRuntime1Mixin.scala
+++ b/daffodil-core/src/main/scala/org/apache/daffodil/core/runtime1/TermRuntime1Mixin.scala
@@ -255,15 +255,18 @@ trait TermRuntime1Mixin { self: Term =>
       val groupedByName = possibles.pnes.groupBy(_.e.namedQName.local)
       groupedByName.foreach { case (_, sameNamesEB) =>
         if (sameNamesEB.length > 1) {
-          SDW(
-            WarnID.NamespaceDifferencesOnly,
-            "Neighboring QNames differ only by namespaces. " +
-              "Infoset representations that do not support namespaces " +
-              "cannot differentiate between these elements and " +
-              "may fail to unparse. QNames are: %s",
-            sameNamesEB.map(_.e.namedQName.toExtendedSyntax).mkString(", ")
-          )
-          hasNamesDifferingOnlyByNS = true
+          val groupedByNamespace = sameNamesEB.groupBy(_.e.namedQName.namespace)
+          if (groupedByNamespace.size > 1) {
+            SDW(
+              WarnID.NamespaceDifferencesOnly,
+              "Neighboring QNames differ only by namespaces. " +
+                "Infoset representations that do not support namespaces " +
+                "cannot differentiate between these elements and " +
+                "may fail to unparse. QNames are: %s",
+              sameNamesEB.map(_.e.namedQName.toExtendedSyntax).mkString(", ")
+            )
+            hasNamesDifferingOnlyByNS = true
+          }
         }
       }
     }
@@ -458,12 +461,15 @@ trait TermRuntime1Mixin { self: Term =>
         // the way one would normally expect a collection to be.
         // So Map[NamedQName, ElementRuntimeData] is not a subtype of Map[QNameBase, ElementRuntimeData]
         // So we need a cast upward to Map[QNameBase,ElementRuntimeData]
-        //
+        // We need the fold because .toMAp overwrites earlier element with duplicate later elements,
+        // but we don't want that, so instead we deduplicate here with earlier elements taking precedence
         val eltMap = sibs
           .map { sib =>
             (sib.e.namedQName, sib.e.erd)
           }
-          .toMap
+          .foldLeft(Map.empty[QNameBase, ElementRuntimeData]) { case (map, (key, value)) =>
+            if (map.contains(key)) map else map + (key -> value)
+          }
           .asInstanceOf[Map[QNameBase, ElementRuntimeData]]
         val resolver = eltMap.size match {
           case 0 => new NoNextElement(trd, isRequiredStreamingUnparserEvent)
diff --git a/daffodil-runtime1/src/main/scala/org/apache/daffodil/runtime1/infoset/PartialNextElementResolver.scala b/daffodil-runtime1/src/main/scala/org/apache/daffodil/runtime1/infoset/PartialNextElementResolver.scala
index 4fbff2460c..9ff51df2af 100644
--- a/daffodil-runtime1/src/main/scala/org/apache/daffodil/runtime1/infoset/PartialNextElementResolver.scala
+++ b/daffodil-runtime1/src/main/scala/org/apache/daffodil/runtime1/infoset/PartialNextElementResolver.scala
@@ -304,9 +304,9 @@ class SeveralPossibilitiesForNextElement(
     hasNamespace: Boolean
   ): Maybe[ElementRuntimeData] = {
     Logger.log.debug(s"""
-      NextERDResovler -> trd: $trd\n
-      NextERDResovler -> looking for: $local\n
-      NextERDResovler -> nextERDMap: $nextERDMap\n""")
+      NextERDResolver -> trd: $trd\n
+      NextERDResolver -> looking for: $local\n
+      NextERDResolver -> nextERDMap: $nextERDMap\n""")
     val optnextERD =
       if (hasNamespace) {
         val sqn = StepQName(
diff --git a/daffodil-test/src/test/resources/org/apache/daffodil/section14/sequence_groups/SequenceGroup.tdml b/daffodil-test/src/test/resources/org/apache/daffodil/section14/sequence_groups/SequenceGroup.tdml
index b4b8d7552c..d0f91b3db5 100644
--- a/daffodil-test/src/test/resources/org/apache/daffodil/section14/sequence_groups/SequenceGroup.tdml
+++ b/daffodil-test/src/test/resources/org/apache/daffodil/section14/sequence_groups/SequenceGroup.tdml
@@ -60,7 +60,7 @@
        Schema: emptySDEschema
       Purpose: This test demonstrates that DFDL allows complexTypes with empty content (not to be confused with NO content)
   -->
-  
+
   <tdml:parserTestCase name="complexEmptyContent" root="complexEmptyContent"
     model="emptySDEschema" description="Section 14 - DFDL-14-007R.">
     <tdml:document>
@@ -1206,12 +1206,58 @@
           dfdl:lengthKind="delimited" />
       </xs:choice>
     </xs:group>
+    <xs:group name="hg_sep">
+      <xs:choice>
+        <xs:element name="inty" type="xs:int" dfdl:initiator="+"
+          dfdl:lengthKind="delimited" dfdl:outputValueCalc="{ 1 }" />
+        <xs:element name="stringy" type="xs:string"
+          dfdl:lengthKind="delimited" />
+      </xs:choice>
+    </xs:group>
+    <xs:group name="vg_sep">
+      <xs:choice>
+        <xs:element name="inty" type="xs:int"  dfdl:initiator="-"
+          dfdl:lengthKind="delimited" />
+        <xs:element name="stringy" type="xs:string"
+          dfdl:lengthKind="delimited" />
+      </xs:choice>
+    </xs:group>
+
+    <xs:element name="root2">
+      <xs:complexType>
+        <xs:group ref="ex:g3" dfdl:separator=","/>
+      </xs:complexType>
+    </xs:element>
+    <xs:group name="g3">
+      <xs:sequence dfdl:separatorPosition="infix">
+        <xs:element name="g3c0" type="xs:string" />
+        <xs:element name="g3c1" type="xs:string" />
+        <xs:element name="g3c2" type="xs:string" />
+        <xs:group ref="ex:hg" />
+        <xs:group ref="ex:vg" />
+      </xs:sequence>
+    </xs:group>
+    <xs:element name="root3">
+      <xs:complexType>
+        <xs:group ref="ex:g4" dfdl:separator=","/>
+      </xs:complexType>
+    </xs:element>
+    <xs:group name="g4">
+      <xs:sequence dfdl:separatorPosition="infix">
+        <xs:element name="c0" type="xs:string" />
+        <xs:element name="c1" type="xs:string" />
+        <xs:element name="c2" type="xs:string" />
+        <xs:group ref="ex:hg_sep" />
+        <xs:group ref="ex:vg_sep" />
+      </xs:sequence>
+    </xs:group>
 
   </tdml:defineSchema>
 
 	<tdml:parserTestCase name="nestedGroupRefs2" root="root"
 		model="nestedGroupRefs2" description="Verify that nested hidden groups and choices work correctly - DFDL-14-039R"
-		roundTrip="twoPass">
+		roundTrip="twoPass"
+    ignoreUnexpectedWarnings="false">
 
 		<tdml:document>
 		  <tdml:documentPart type="text" replaceDFDLEntities="true"><![CDATA[A,B,C,1,x|D,E,F,2,y|G,H,I,3,z%LF;A,B,C,x,1|D,E,F,y,2|G,H,I,z,3%LF;A,B,C,4,u|D,E,F,5,v|G,H,I,6,w]]></tdml:documentPart>
@@ -1286,12 +1332,81 @@
 
   </tdml:parserTestCase>
 
+  <tdml:parserTestCase name="nestedGroupRefs3" root="root2"
+                       model="nestedGroupRefs2" description="Verify that nested groups and choices work correctly - DFDL-14-039R"
+                       roundTrip="onePass"
+                       ignoreUnexpectedWarnings="false">
+
+    <tdml:document>
+      <tdml:documentPart type="text" replaceDFDLEntities="true"><![CDATA[A,B,C,1,x]]></tdml:documentPart>
+    </tdml:document>
+
+    <tdml:infoset>
+      <tdml:dfdlInfoset>
+        <root2>
+          <g3c0>A</g3c0>
+          <g3c1>B</g3c1>
+          <g3c2>C</g3c2>
+          <inty>1</inty>
+          <stringy>x</stringy>
+        </root2>
+      </tdml:dfdlInfoset>
+    </tdml:infoset>
+
+  </tdml:parserTestCase>
+
+  <tdml:parserTestCase name="nestedGroupRefs4" root="root2"
+                       model="nestedGroupRefs2" description="Verify that nested groups and choices work correctly - DFDL-14-039R"
+                       roundTrip="onePass"
+                       ignoreUnexpectedWarnings="false">
+
+    <tdml:document>
+      <tdml:documentPart type="text" replaceDFDLEntities="true"><![CDATA[A,B,C,x,1]]></tdml:documentPart>
+    </tdml:document>
+
+    <tdml:infoset>
+      <tdml:dfdlInfoset>
+        <root2>
+          <g3c0>A</g3c0>
+          <g3c1>B</g3c1>
+          <g3c2>C</g3c2>
+          <stringy>x</stringy>
+          <inty>1</inty>
+        </root2>
+      </tdml:dfdlInfoset>
+    </tdml:infoset>
+
+  </tdml:parserTestCase>
+
+  <tdml:parserTestCase name="nestedGroupRefs5" root="root3"
+                       model="nestedGroupRefs2" description="Verify that nested groups and choices work correctly - DFDL-14-039R"
+                       roundTrip="onePass"
+                       ignoreUnexpectedWarnings="false">
+
+    <tdml:document>
+      <tdml:documentPart type="text" replaceDFDLEntities="true"><![CDATA[A,B,C,x,1]]></tdml:documentPart>
+    </tdml:document>
+
+    <tdml:infoset>
+      <tdml:dfdlInfoset>
+        <root3>
+          <c0>A</c0>
+          <c1>B</c1>
+          <c2>C</c2>
+          <stringy>x</stringy>
+          <stringy>1</stringy>
+        </root3>
+      </tdml:dfdlInfoset>
+    </tdml:infoset>
+
+  </tdml:parserTestCase>
+
   <tdml:defineSchema name="noDefault">
     <xs:include schemaLocation="/org/apache/daffodil/xsd/DFDLGeneralFormat.dfdl.xsd"/>
     <dfdl:format ref="ex:GeneralFormat" lengthKind="delimited" />
 
     <xs:element name="emptySeq" type="ex:complexEmptySeq" dfdl:lengthKind="implicit"/>
-    
+
     <xs:complexType name="complexEmptySeq">
       <xs:sequence/>
     </xs:complexType>
@@ -1302,7 +1417,7 @@
        Schema: emptySDEschema
       Purpose: This test demonstrates that DFDL allows complexTypes with empty content (not to be confused with NO content)
   -->
-  
+
   <tdml:parserTestCase name="noDefaultSeqKind" root="emptySeq"
     model="noDefault" description="Section 14 - DFDL-14-007R.">
     <tdml:document>
diff --git a/daffodil-test/src/test/scala/org/apache/daffodil/section14/sequence_groups/TestSequenceGroups.scala b/daffodil-test/src/test/scala/org/apache/daffodil/section14/sequence_groups/TestSequenceGroups.scala
index 819d0fc2ee..873eb6e7b9 100644
--- a/daffodil-test/src/test/scala/org/apache/daffodil/section14/sequence_groups/TestSequenceGroups.scala
+++ b/daffodil-test/src/test/scala/org/apache/daffodil/section14/sequence_groups/TestSequenceGroups.scala
@@ -106,6 +106,9 @@ class TestSequenceGroups {
   @Test def test_hiddenGroupNested2(): Unit = { runner_02.runOneTest("hiddenGroupNested2") }
   @Test def test_nestedGroupRefs(): Unit = { runner_02.runOneTest("nestedGroupRefs") }
   @Test def test_nestedGroupRefs2(): Unit = { runner_02.runOneTest("nestedGroupRefs2") }
+  @Test def test_nestedGroupRefs3(): Unit = { runner_02.runOneTest("nestedGroupRefs3") }
+  @Test def test_nestedGroupRefs4(): Unit = { runner_02.runOneTest("nestedGroupRefs4") }
+  @Test def test_nestedGroupRefs5(): Unit = { runner_02.runOneTest("nestedGroupRefs5") }
   @Test def test_hiddenGroupChoice(): Unit = { runner_02.runOneTest("hiddenGroupChoice") }
   @Test def test_hiddenGroupChoice2(): Unit = { runner_02.runOneTest("hiddenGroupChoice2") }
   @Test def test_hiddenGroupIgnoredProps(): Unit = {