Hi @rick-kramer_9238,
I'm really not sure what the underlying issue is or how to troubleshoot :(
NuGet dependency resolution is really complicated, and what you're saying is probably related. If you get a "package/version cannot be found" error from the NuGet client, it doesn't necessarily mean that the version isn't there... jsut that the dependency search wasn't successful.
You can just look at the ProGet server to see what packages/versions are there. If it's in the UI, iut will be in the API.
Cheers,
Alana