I don't know if he was a sex offender, I tend to think he was not. He would settle such case because sometimes you just can't risk the loss. Admittedly, he put himself in a bad situation.
However, if he was a child sex offender, I believe a lot more kids would have come forward over the years, a lot more.
He was weird based on societal standards, but I think he was just more comfortable with kids. Kind of a recluse. He sure fucked up what should have been a great life.