His mistress (now wife) came to his HS games and sat in the stands not too far from his then-wife, but I don't know where you are getting the cheerleader BS. She was definitely of age.
Wasnt a mistress, he had two entirely different families, wives, kids, etc. His background check at the University of Alabama for an analyst job is where he was found out, they saw two different addresses and did some checking. He was basically hired by Saban out of Hoover HS before this come up, instead UA hired a different coach from Hoover that year, Jeremy Pruitt.