Hi, @Michael Menzie
Thank you for posting in Microsoft Q&A forum.
If an account has ever been configured as an NAA, its credentials may be on disk, you may check this link for more details:
https://posts.specterops.io/the-phantom-credentials-of-sccm-why-the-naa-wont-die-332ac7aa1ab9
(Please Note: Since the website is not hosted by Microsoft, just for your reference.)
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