I have no idea who he is but he sounds like a trouble maker. You are right about his trading, he is fine with it if it when it suits him.
I did read an article that he has done this before on the show and he was willing to the help owner to return their item back to Africa.
My advice is this, if you got an item instead of going to the show just take it to an auction as a gamble. Things are only worth on what people are willing to pay.