Are we positive the account was enabled? If what I think happened, happened, then they dumped Active Directory password hashes, in which case you don't see the account status by default when using popular tools. I sometimes do password analyses for corporations, and in the beginning, when I reported a few particularly weak passwords of particularly powerful accounts, they often told me that this was an account which had been disabled years ago, so this wasn't useful information to them. Eventually I started filtering out disabled accounts.

Then again, it sounds like this organization had many issues. (Why was the former employee's account still enabled? Why didn't they mandate MFA?)