question

Assuming you are referring to https://docs.microsoft.com/en-us/troubleshoot/mem/intune/troubleshoot-co-management-workloads, what exactly is lacking?

@KeithChalmers-3234, To troubleshoot co-management: Auto-enroll existing Configuration Manager-managed devices into Intune issue, we can refer to the following article:
https://docs.microsoft.com/en-us/troubleshoot/mem/intune/troubleshoot-co-management-auto-enrolling
http://thewindowsupdate.com/2019/09/03/support-tip-understanding-auto-enrollment-in-a-co-managed-environment/
Note: Non-microsoft link, just for the reference.

For workflow issue, we can refer to the article Jason provided.

Hope it can help.

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