Spoilers I just realized on my nth viewing
There IS actually a happy ending for Cliff. Judah tells him the story at the end of the wedding, and then Cliff went out and turned it into Crimes and Misdemeanors! The film is his success story.
shareCould be except Cliff is a dedicated documentary filmmaker
Besides, his cluelessness is demonstrated by the fact that he dismissed Judah’s story as not film-worthy ... even though he himself is a (collateral) character in the exact film Judah is describing