I am curious about the ADA argument though. How would Summitt's be protected by the ADA ?
We have some people around here who might be equipped to answer better as specialists in employment law, but here's my take.
I think an allegation that the University violated the ADA (assuming it forced Summitt out) would be rather conclusory on the plaintiff's part. The Americans With Disabilities Act would protect someone from being fired on account of her disability IF she could still do the job with or without accommodations.
Not all people with Alzheimer’s disease will need accommodations to perform their jobs and many others may only need a few accommodations. There are zillions of possible accommodations that might be efficacious, depending on the stage of the illness and the nature of the job. Some of those already appear to have been made during Summitt's later years as as head coach.
But if plaintiff is making a whistle-blower argument -- that she was fired for arguing that it would be illegal to fire someone else -- that gets into another area.
Maybe she wouldn't have to prove that she was right on the law (in effect, having to go through two court proceedings) but only that she was plausibly urging compliance with the law -- in response to which the evil employer, bent on lawbreaking and not appreciating the advice from the peanut gallery, gave her the boot.