On the few facts available here, it would seem that McCotter delegated the collection of signatures to someone, and that that someone was in the other camp and submitted false signatures. At least that’s how it reads so far.
Now, granted, McCotter should have taken a bit more interest in an action that would determine his future, but still, this sounds like he was sandbagged somehow.
It seems like someone in the last few steps of the chain to submit the signatures was up to no good. McCotter is my rep too. I heard him speak at our first tea party rally. It was a short but great speech.
Maybe he can crack the whip in his last few months in office.