amurray
We don't have a docker container. The one you are using is made by a 3rd party and we (core osTicket developers) have no association with it. We do not use Docker at all internally.
I will say your client ID looks totally incorrect and your attribute mappings might be incorrect as well. You will need to inspect the response back to osTicket from the IdP to see the attributes it's sending. Also, the Agent must exist in the system before attempting to authenticate in osTicket.
Cheers.