Hi Lori,
Within your specific application you are auditing one thing that might be a good starting place is to go into your users table and use the dynamic filter for Status. One option is to pull all the users in that user table who are deactivated. That would help to narrow down to just the users listed in your users table who are marked as deactivated. Ideally that would give you a smaller pool to then search for in the application. You wouldn't be checking a user list at the Account level. I hope that suggestion is helpful.
Currently there is not a formula function to ascertain a users status within the Account or a reporting filter for user status.