(I hope this makes sense, I'm tired...)

I don't remember that part of the film, but if that's what they portrayed him as particularly uninterested in abolition that's incorrect. However, attitudes towards slavery among revolutionaries was often surprisingly lukewarm. Many who are praised today for working against slavery fought against that "accusation" during their lifetimes, like Olympe de Gouges and Brissot. The reason for this is the importance of the colonies, and it was assumed that liberating slaves would lead to France losing them. Accusing your enemies of wanting to end slavery was a cheap way to raise suspicions, which is the reason for the denials I mentioned. Robespierre did that briefly in a speech against Brissot in 1793. In 1791 he said pretty much what everyone else was protesting the accusation of saying, declaring that accepting slavery would lead to the ruin of French democracy and that slavery had to be abolished even at the expense of the colonies.

I can't really explain the difference between these two statements. Either way, the statement he made against Brissot, accusing him of wanting to "at once free and arm slaves in order to lose [our] colonies", was aimed at (what Robespierre assumed to be, at least) the opinion in the National Assembly, which was apparently happy enough to preserve slavery that this was a reasonable slander.