CPY dll flagged and deleted by Windows Defender?

I grabbed the latest iteration of the Annual Parkour Murder series, and have over 40 hours logged already. Today, I tried to boot the game only to find that WinDefender had deleted the dbdata.dll file from my install directory, and won't let me re-copy it into place from the install ISO. It also throws the SAME error when I try to add it to the Exclusions list.

How do I tell Defender to fuck off in this case, but keep running otherwise?