Putting a custom symbol in only one item value within the Tooltip

[gjrogala]

I followed this YouTube tutorial that shows how to include a custom dollar sign in the Y axis value as well as the tooltip item but I struggle to apply this only to one tooltip value.

I have a multiline chart that has two Y axes and only one of these has a custom sign next to the values. So in my tooltip I have two items. I figures out how to add a % symbol to only one Y six values via callbacks but struggle to apply the same approach the corresponding item in the tooltip as there are two items there.

CodePen example here (first chart from the top)

Thanks for your help!