Your view seems to be that there was a sex crime, and that the alleged victim was subject to some sort of harassment.
There is another possibility, and before I go any further I acknowledge that this is a contentious point. But it happens to be a serious one as well. So, let us suppose that in fact Lewan knows something that we don't; that he somehow knew that the allegation made against his friend and teammate Gibbons was false. I know that I'd be pretty hacked off, to see a friend or teammate go through what Gibbons has, under false pretenses. At the age of 19 or 20, I might say something intemperate among my buddies.
You "can only imagine" the effect it had on the complainant. I agree with you. You can only imagine, because we don't know. You have to "imagine," absent our seeing testimony from her, under oath and under cross-examination by an opposing attorney.
I have no problem with protecting complaining witnesses in sexual/domestic abuse cases. The criminal justice system knows how to handle such matters; they do it all the time. There may be complaints; it may not be a perfect system. But the criminal justice system is how we carefully balance the rights of the accused with the interests of the accuser, and it is how we gauge criminal guilt.
Let's remember one more thing about Gibbons. He was in Ann Arbor for another four years after the incident in question. As far as I know, this sort of incident was never repeated. The notion that there was a cabal of Michigan football players at work, attacking coeds and silencing critics through threats, is baseless.