The moral of this story wasn't "here is a person who is evil", or even "here is an event that doesn't do a good enough job to keep stuff like this from happening" (is the event even named?).
The moral of the story is "this stuff happens, and this is what it is like for people who experience it".
You may just have to live with the fact that there's no way to interrogate her account without sounding like a creep.