One question we need to REALLY ask with regards to ANY Hunchback adaptation is “Are certain characters really necessary to over-all version of the story that the movie is TRYING to tell?” With Quasimodo d’El Paris the main focus is making the movie a modern comedy while still trying to be accurate. This means the movie NEEDED Gringoire as he is both in the original story and one of the lighter characters but does the movie do much with him? Nope.
Gringoire starts the movie as the ignored entrainment at Agnes’ birthday party. He then get’s drunk and him and Agnes wonder around and run into the Cuban. The Court of Miracle scene occurs and they are married and that is pretty much it for Gringoire. He kind lurks around Clopin after that and acts the coward and a bit of a dummy.
He is not fully a side character or used for decent comedy, every one is being silly in some way so what different if he says cowardly/goofy/weird things once in a while. Esmeralda could have let him die and it wouldn’t have changed much in the narrative. So was he necessary for this version? Not Really but I wished he had done more, I feel like their was wasted potential because point for point when he was doing more in the movie he was a decent version of the character just super underutilized in the 2nd and 3rd acts.