I also truly believe if any of these guys did anything their lawyers would have advised them to claim some kind of consensual sex--instead they ALL say no one touched her.
That's how four guys from the University of Minnesota basketball team got away with raping a girl in Wisconsin (Madison, I think) back in the 80's. With the first player, it actually WAS consensual - with the other three, it wasn't, but with the collapsed lung they gave her, she couldn't do much towards fighting them off. I originally believed the AV in this case, but her story's completely melted down.