@Geoff B Thanks for posting in our Q&A.
For this issue, I have noticed that there are many additional apps. It is suggested to try to remove the target user which is used to enroll this android device from these apps' assignment before doing the COPE. Then check if this enrollment stuck situation will still exist.
It is suggested to deploy these apps to the Android device after finishing enrollment.
If there is anything update, feel free to let us know.
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