Baseball Umpire Signals

What’s the ruling on this play?
Bases loaded. Bottom of the 9th. Visiting team is leading 4-1. 2 out. Batter hits an apparent grand slam homer, but the runner at first misses 2nd base. The second baseman notices, and calls for a new baseball. He touches 2nd, and the umpire signals out. Does the batter lose the home run? Do the runners at 2nd & 3rd score? Does the home team lose?
No runs score because the out at second was a force out, and most of the answers above me are jokes.
Frizzer, please stop embarrassing yourself. Your ruling is totally wrong.
KDII’s answer is full of nonsense.
Jeremy, the batter-runner did not pass the runner from first.
Bad call by the umpire in a tnc youth baseball semifinal game. Cost the kids the game