Well, I think we can all agree that at the age of 19, we didn't use alot of common sense( like jumping of a cliff into a reservoir, just to name one ). Also, this wasn't some sleazy motel in New York. I believe it was a resort(and a pretty plush one at that) and the girl worked there. But the bottom line is that our opinion on what she should have done is not the point. When a woman says no, you stop. And if you don't, it's sexual assault.
Now i'm not saying he did force himself on her, but if he did, it's sexual assault, no matter when she said no.