In that new rule video I posted earlier they showed the Arizona/Seattle game where the AZ receiver caught the ball, took 4 steps as he was going to the ground and the ball came out. It was ruled a fumble, then changed to GTTG after replay. Same rule, same subjective call reversed. Why could that one be reversed between a completed catch and GTTG applied later but the Dez call could not? You keep trying to create this "they can't review a subjective call" rule with no citation. Do you have one? Where in the rules does it say you can't overturn a subjective call? There's literally an example on a "GTTG or not" play that says otherwise. Same for calling a run a 1st down when it was subjectively spotted short at first and overturned on replay.
What you're ignoring is the on-field ref could have ruled GTTG but didn't see the ball touch the ground where Dez would still be down at the 1 because in that case he had control, was contacted, and survived the ground and rolled over before the ball came out of his hands. If he didn't see it touch, then the player is ruled down where you survived the ground (at the 1). Anything else is post-bounce/slide/rollover YAC including scoring a TD from such. Zero basis in the rules for it unless you have a citation I keep asking for. Have any?