I just rewatched it multiple times...I'm not completely clear on the rule, but it did appear that the play should have still been live at the point you reference. It was Nick Perry BTW. Perry picked up the ball and began walking as if the play was over and so did most other players. When Perry had the ball knocked out of his band, even most of the Cowboy players had already stopped playing, but I don't think there was any reason to stop play at that point. The ball was thrown backwards and hit the ground which I believe is still a live ball. Perry picked it up but should have secured it by hitting the dirt.... he didn't.Dud is whoever the guy was on the last play of the game who picked up the ball like it was incomplete and got it knocked out of his hands and let the laterals continue.