@Anthony Banks Thanks for posting in our Q&A.
Honestly, not sure why some macOS devices failed. It seems needed to check some logs to find the cause. With Q&A limitation, Q&A is not a good channel for such issue. It is suggested to create an online support ticket to get more help. Here is the support link:
https://video2.skills-academy.com/en-us/mem/get-support
Or you can do "delete" action to instead "Retire" action, it will remove these devices immediately.
Hope it will give you some ideas.
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