Good work there; however, there is another part of the rule book that is very specific the this situation. Forward progress was reviewable in this situation. The refs said is wasn't because they did not know the rules.
Rule 12. Instant Replay
Dead Ball and Loose Ball ARTICLE 3. Reviewable plays involving potential dead balls and loose balls include:
e. Ball carrier’s forward progress, spot of fumble, or spot of out-of-bounds backward pass, with respect to a first down or the goal line.
So, by rule, it should have been reviewed and a touchdown.