Gene Steratore about the play.
"Although the receiver is possessing the football, he must maintain possession of that football throughout the entire process of the catch," Steratore said. "In our judgement he maintained possession but continued to fall and never had another act common to the game. We deemed that by our judgement to be the full process of the catch, and at the time he lands and the ball hits the ground, it comes loose as it hits the ground, which would make that incomplete; although he re-possesses it, it does contact the ground when he reaches so the repossession is irrelevant because it was ruled an incomplete pass when we had the ball hit the ground."
Notice his statement: "by our judgement." It was a judgment call. The real question becomes did Dez make "another act common to the game." How can anyone say that reaching for the goal line is not "another act common to the game"?
Either way, I do not think there was enough evidence to overturn the call.