Maybe he could have tried to get on the documentary bandwagon before Wrexham did, then reap the bigger sponsorships when Salford were riding the wave of publicity. That he didn't might hurt, and it's too late now as it's already been done.
It literally wouldn't have been as Hollywood though, the only way to do it would have to get Beckham really on board but even then I'm not sure it would have all had the same pulling power. Doubt it would have got the American interest the way Wrexham have.
Salford being being a naturally smaller club is another big difference. They'd never get those attendances even if the stadium was big enough. There's a bit less romance/mystique with Salford too if you were trying sell their story, the hard-working mining town whose club has fallen on difficult times versus the never-were-anythings, albeit from a very working class background as well.