Auth0 using on 2 domains

Hello,

We have a massive issue which we need desperate help.

We have our Group company, lets call it company A, who owns Company B (where I work). Company A currently utilises Auth0 to authorise users to an application we run internally via GCP Auth 2.0.

We are separating our Google Workspaces instances NOT GCP from Company A. We will still remain a subsidiary of Company A, but Company B is independent. We still need to leave our Auth0 instance where it is as Company A uses it, but we also want to retain ALL our users data when we move our domain away from Company A’s Google Instance.

I have tried replicating client ID from GCP into our new Google Workspace isnatnce (Company B) but I get the below error

Auth0 is restricted to users within its organization. If you think you should have access, you can contact the developer. Learn more about this error
If you are a developer of Auth0, see error details.
Error 403: org_internal

We really just want to retain the user information because Auth0 creates the user and gives them the relevant roles and we want to avoid creating over 1000 of new users.

Any help is trully appreciated.