unreal_material_parameter_* for landscape doesn't change custom parameters on created instance material

[mudakisa]

Reproduction:

• HDA includes heightfield
• unreal_material_instance set to existing material in Unreal
• unreal_material_parameter_*** set to the corresponding custom parameter

In the Unreal after cooking creates a landscape, creates instance material, assigns it to the landscape...
But the parameter isn't activated (toggle still false) and the parameter value stays default.

If replace heightfield on static mesh - all works fine. But with heightfield/landscape - no.

Houdini 20.0.625 (Houdini Engine installed from this build), Unreal 5.3.2