It's not a slam dunk and I don't ever call cases that. Many a slip between the cup and lip. I will say that I have taken more difficult cases and been successful. All of these cases hinge on perception and character.
Your version of the head coach's duties and mine differ. He might not be calling plays but he's damn sure watching them and the OL gets lots of his attention. If his position is he didn't notice I would make him look incompetent. An expert would be hired, a former coach, to testify that it is damn near inconceivable that Butch didn't notice. It's not a slam dunk, but I am confident I could convince a jury and perhaps more important it provides me leverage.
The difficult aspect of this case is damages. In this case they are uncertain, but the university is going to have a tough time fighting you on this aspect in the court of public opinion. Essentially, you would show the jury that every concussion causes brain damage. Every single one. Even a single concussion can cause permanent brain damage. Blows to the head while suffering the effects of a concussion exponentially increases the odds of permanent brain damage. The NCAA instituted a concussion protocol to specifically avoid the occurrence of multiple concussion in small time frame. UT via it's Jones and Wells deliberately ignored the protocol placing Brett at risk for multiple concussions. I would advocating for punitive damages.