home games I believe, the cards should speak for themselves. I would not tolerate someone just pulling the chips to them hoping that the person who actually won wouldn't say anything. The dealer I believe, has every right to step in and declare the winning hand. In my home games, we are all friends. no one has ever tried to pull a fast one, ever. if anyone did, or if there was a bit of confusion initially then I would expect anyone to jump in and say a mistake has been made, and between us, the person who thought he'd won would have no issues with it.
I would tell him to shut up and not to bother coming if he does that again (if indeed he has clearly tried it on numerous occasions). you did everything right. you're the dealer so you should intervene.