It's funny how our desire to pretend this isn't true has ebbed and flowed over the years.
This is pretty different than the usual buyout-dodging "oh but we're actually firing him for cause because of a trumped-up NCAA scandal" stuff, IMO. That has a certain fig leaf of puffing up the athletic department's compliance process.
An esteemed public university unilaterally publicizing an extramarital affair by one its two dramatically most prominent and highest paid employees is quite different, some seriously ugly business, it's unambiguously blackmail, and if I am Walters' agent I would have a very strong suspicion Purdue is bluffing about their willingness to really go through with it.