I don't think it happened, but I don't think she's lying. I assume she's filling in details from a traumatic experience that she didn't talk about for decades. Nobody else remembers what happened the way she did and its not like minors in a college party are in a good state of mind for perfect recall. I'm not really inclined to take her word as gospel with nothing else even sort of supporting it and nothing likely to emerge supporting it either.
"I don't want to look callous so I'll say I "believe" her, but I'll edit what she's saying selectively so I don't have to actually hold anybody accountable who agrees with me politically."