The bathing suit actually sounds like the kind of thing one wouldn’t think to invent. Perhaps she was once groped at a party to which she’d gone after swimming.
I don't think so. It reminds me of Ferris Bueller's excuse to get out of school. You use details that can be remembered but not quite enough to get sent to the doctor. Rough equivalent to licking your palms...
The suit is not a bathing suit but rather a chastity suit
I get the impression that the party was held at a private residence in Maryland. I don’t know if that has been confirmed or not.
If so, and the house had a pool, it’s quite possible that she had been swimming. There is nothing unusual about pool parties. It would be helpful to know what time of year it was. If mid-winter, I would be skeptical.
If she had been swimming at another location, she would have changed into street clothes before going to the party.