Full error: "Cross-deployment Admin API usage through Accounts API is currently not available, please refer to: https://duo.com/docs/accountsapi#using-accounts-api-with-admin-api"",
Steps to Resolution
This error indicates the Child Tenant is not properly setup beneath the Parent inspector on the Duo side.
Duo recommends reaching out to your Account Manager or their support team to make sure the Child Tenant is properly setup.
Provide Duo support with the above error and the tenant in question, and they should be able to assist you further.
Outcome: Once Duo successfully migrates the tenant, the inspector should complete normally