Depends upon what they focus on. One of Goodells big lies was the independent investigation lie, however in their filing to Bermans court Pash claimed the investigation was neither independent not did it need to be. They were having their cake and eating it.
I don't think this rehearing, if they get it, is going to be about the investigation though, I think it will be about Goodell handing down punishments for things that were not a part of the appeal, specifically the phone, which Goodell claimed was similar to PEDs this upholding the 4 game suspension. However the initial punishment had nothing to do with his phone, that came up right before the appeal. So Brady, in effect, never got to appeal what he was ultimately punished for. That's the "industrial justice" Feinberg is alluding to.
Imo this is why Brady is going to win in the end. All Goodell had to too was rule that the initial punishment was upheld and the NFL would most likely win, unfair as that would be. However Goodell's hubris and incompetence led him to instate his own rulings rather than simply uphold the ones they had already put in place.
He's a f.cking idiot, case closed.