Been going back and forth with Apple Enterprise Support and PowerSchool Support over how to make the initial settings work for the connection as we were having issues of no joy. After trying every known variation for the base URL, and several support calls, we determined the issue was rather simple.
So, word to wise... If you host the PowerSchool server onsite, you must have a SSL Cert in place. Your PowerSchool server will not release the needed OAuth token nor the data needed without a SSL Cert.
No cert, no ASM sync. Simple enough. If you cannot access PowerSchool via HTTPS, that is an indication you are not set for SSL.
Hope this helps someone out there.
Will update as warranted.

