Bad move IMO. The two guys who shared the bathroom will now have DNA tied to the alleged crime scene. A little victim coaching, and we have two suspects to charge. Email guy probably becomes the third.
Something else was curious to me. 46 white players gave their samples, but according to reports three of them were in NYC when this supposedly occurred. I'll assume these three gave DNA as a show of support to those that were at the party? If so, it is telling that team member 47 didn't also volunteer. Does he know something? Or is he afraid to publicly show support for his teammates, regardless of if he knew the charges were bunk or not?
In a sane world, finding DNA on a bathroom towel is perfectly normal as people do tend to dry their hands off after washing them.
Unfortunately, you are probably right - Wendy Murphy and Nancy Grace are already hawking this as semen. The email guy will probably be the third just like you said. Of course, they will take his words out of context to do it.