To be honest with you...unless that yearbook message was something along the lines of, “Sorry about that unfortunate incident behind the restaurant—better put some ice on it,” I don’t see how it is incriminating in the least.
How many famous people sign autographs and remember the person who asked them? Are we to infer that every autograph is possible proof of sexual assault?
I agree. It would prove that she knew him. Even that is now in doubt, given that the yearbook looks so contrived.