Things aren't always the way they may appear to be. Unless you have concrete proof of his wrong doing, you are far better off to keep your mouth quiet. I know it sucks to do so. I understand your situation, I have had similar situations and the best advice I was given by a couple guys that aren't on here much any more and a few that are, run your business on the up and up and how you want and need to and let others do the same. The more time you spend worrying about the guy down the road could be better spent on your business. Show folks that you are the better option.