It was bobbled against the ground... but he had crossed the plane. I guess they decided that the pass-catching completion rules dominated the passing the goal-line plane rule.
Even the announcers were surprised. Romo said, “Oh... that’s what they’re discussing on the review”, after first saying “Touchdown!”.
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Yes.
Anyone over the age of 35 or 40 who has seen a lot of footall in their life would KNOW that was a good catch. His veryslight bobble as the ball and his hands touched the ground IN THE END ZONE is meaningless.