The student doesn't care what belt they are, or when they test for black belt. They just want to train. That said, they are understandably uncomfortable with the questions being demoted will cause, so I think the more just course of action is to have a longer than usual period of time between double black stripe and black belt. That decision isn't mine though.
Honestly, I don't know why this has been made such a big deal. The university club is struggling for consistency and dedication from its instructors, but apparently it's more important to create drama over something so petty as a colour belt test.