No, I agree with the person you're responding to. Saying "I refuse to play with known cheaters" is better than "He's cheating and so I don't want to play with him". With the letter you suddenly have to prove something really difficult. With the former you have absolutely nothing to prove.
But.... that is what he said. Please highlight the part of the statement where he said something that was closer to "he is a known cheater" vs. "he is cheating".
