Why Tommy Wiseau Had To Cameo in The Disaster Artist
The Disaster Artist is based on Greg Sestero's co-authored book of the same name about the making of The Room. However, to actually produce the movie, Franco needed to get Tommy Wiseau's life rights. Typical of the New Orlean's eccentricity, Tommy agreed but with some conditions. The first was that a producer would listen to his notes after seeing a rough cut, easy enough when there was no obligation to follow his feedback. The second, however, posed an issue: Tommy wanted a cameo in the film alongside James Franco's version of him.
Plenty of funny ideas for how to integrate Tommy into the film were brainstormed (per The Wrap, who interviewed screenwriter Scott Neustadter, they considered having him a friend of Greg's) but eventually, it was realized there was no way to fulfill the contractual obligation in the narrative of the film itself. So, the filmmakers instead opted for a standalone scene after the credits where the two Tommy's would engage in what was known on set as "dueling Wiseaus". That way, Franco could break the fourth wall without making the for-the-most-part-grounded movie struggle.
Ultimately, it's a funny scene and one that feels like a special reward for long-standing fans of The Room: for those who've been to the regular screenings around the world, there's little difference to seeing Tommy meet Tommy than there was Tony Stark meeting Nick Fury back in 2008's Iron Man. That's not to say there weren't stronger alternatives; some would have definitely liked to have Tommy playing James Franco in a recreation of the rights deal that led to the scene, an unparalleled meta gag. However, with Wiseau reportedly also getting refusal on the character and choice of costume, that simply wouldn't have been logistically possible.
As for Wiseau's other part of the deal, it seems like he didn't have many objections to the frank movie on his folly-turned-masterwork. He didn't see the completed picture until it screened at TIFF, by which point Sestero had given it his approval and critics were already praising it as one of the year's best. Nevertheless, this was a nervewracking experience for James and Dave; Wiseau had previously claimed the book was only partially true, and with that having been their blueprint the brothers were expecting the worse. However, Wiseau didn't have any major complaints with the film (publicly at least) bar some critiquing of how Franco lit some of the earlier scenes, a complaint he's since doubled back on and replaced with an issue about how James throws the football.
That anecdote, of course, is rather tongue-in-cheek, but then again so is the entire post-credits ephemera and, if we're being honest, the entirety of The Disaster Artist. It's a love letter to something so awful it provides ironic joy, done with all the sincerity of a biopic of a true great.