Several problems with the date rape drug theory--1) the accuser would not be able to confidently id her attackers 2) she would not be able to put a herculean struggle the way she claimed, and 3) she also would not be in any condition be hollering and screaming at the hospital not long after.
So by trying to plug a hole, this theory only creates others.
Oh, I think that in this case it was a fairly violent assault that started because of an argument over money. However, most of the rapes in college are date rapes fueled by alcohol and sometimes date rape drugs.