Hey @PatrickMast - I wonder if what you're finding is that Public Apps aren't supported on-prem, while we instead recommend on-prem customers use our Portals or Embed features instead? Info on that change posted here.
Regarding credits I believe you were able to connect with our team directly a few weeks ago 
Startup credits are meant to be applied to just one instance, not split. If you've still got most of your credits left we should be able to do a one-time transfer to a different org if you choose to use them for a different org.