If someone calls my office and tells me that one of our customers is doing something illegal, I will not, under any circumstance, forward that information to law enforcement. Why would I? All I have is an unproven accusation by someone I know absolutely nothing about! What, exactly, is stopping the person making the accusation from calling the police himself, instead of me? Why is he contacting me - is that because contacting the police would get him into legal hot water? If so, would it be wise for me to act as his unpaid proxy in this? No, of course not!

Again, we still don't even know if the person making the accusation is in fact the injured party, or guilty of the very fraud he is accusing the other website of! Why are you trusting him at all? You don't know either party, you don't know the websites, so what are you basing your preference on?