@Alan Feistner
Hi,
Based on your description, I want to confirm that have you made any changes before the problem occurred?
We could try to repair BitLocker first and decrypt again in clean boot to check the result.
Using the BitLocker Repair Tool to Recover a Drive:
https://technet.microsoft.com/en-us/library/ee523219(v=ws.10).aspx
Hope above information can help you.
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