They can definitely tell if she had sex with anyone else within a day or so. If they took her to a hospital they probably have swabs and enough to tell if she had been with more then one guy. I doubt they can tell if it was before or after, but they may be able to narrow it down to one or the other by statements she gave and knowledge of her whereabouts that day.
Rape isn't about sex it is an act of violence. The method is just different then an asshole hitting someone. I have serious doubts about this whole case. It seems she gave it up willingly and then decided at the end or after wards she could make a lot of money off this kind of like a Monica Lewinsky. I saved the dress with the Presidents spunk on it. That's just gross.
