@Keith Trodd Thanks for posting in our Q&A.
As I didn't have the test device, and I can't repeat this issue. After researching, I didn't find there's any setting in Intune side to clear the credential. Given this situation, it is suggested to create an online support ticket to find if we can get more help. Here is the support link:
https://learn.microsoft.com/en-us/mem/get-support
Thanks for the understanding.
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