Not necessarily foul...just weird. It was an unofficial visit, she left during the game without having some sort of closing conversation with the staff, and then committed the next day. I could see if she committed after an official visit, but this sequencing seems like an impulse decision (or she had made her decision before the visit).
I think that Cambridge will pick a school where she isn't going to be designated as a backup for her career. I can see her willing to be a role player for 1, maybe 2 years...but will expect to be starting as a junior. So...no UConn, Stanford or SC because all will likely have top tier PGs in the class ahead of her.