Touchdown Rule: a question

[WaRef]

This was one of those situations that even a 7-man crew cannot adequately cover. In "reverse mechanics," not many of us can run 70 yards with the professionals and be on the goal line for the call. The replays, also, did not have a definitive angle to determine whether the ball went out of bounds before or after it crossed the goal line. As mentioned in other threads, had the ruling been that the ball crossed the goal line first, it would have been NE ball at the 20. There was a somewhat similar situation in the Chicago/Carolina game, but a penalty negated the touchback.