"He didn't harass women during the two days I interacted with him, therefore he has never done so" is not as strong a defense as you seem to think.
Exactly, he's innocent until proven guilty, like everybody else.
You're implying that "I heard from someone that heard it from someone else, that heard it from their dad, that read it on a mailing list, 20 years ago, that he did, therefore ho did"