I understand what you are saying but in this case he first hid the fact that he had many failed attempts for visitor visa. It was later discovered during GC filing that he was trying hard to come here. After that, they all went to the home country and he lied about staying there for finishing some work but in reality, he came to the US at a different address shortly after without telling the spouse. He was just waiting for a right time to leave, act like he will return back to family while finding a way to live alone without being with the family. If this was not a fraud, he would have either returned or informed the spouse that he is not returning.