Given that he's been the coach for 20 years, wouldn't something have come out before now if these allegations are true?
Probably not the most bulletproof logic, considering how long the issues at Penn State carried on before being leaked out, the current prep school scandals on the East coast (just now letting go faculty members who committed sexual assault and molestation of students in the 70s, 80s, 90s), and NCAA investigations like the UNC Academics issue which goes all the way back to 2002.
That said, Fennelly has a reputation of being a hard-*** on the court and great to players off the court. He's not going to jive with everyone all the time or even a majority of the time. His job is to put the best players on the court that he can in order to win games, and help develop young women into successful adults on and off the court. But the young women have to play along as well and do their part to heed advice, listen to criticism, etc.