They'd never retcon Ghostbusters II. Sure, it wasn't critically well-received and it got overshadowed by Batman when it came out, but the worst thing anyone says about it these days is "it's not bad but it's nowhere near as good as the first one". My question is if they'll make some sort of reference to the Ghostbusters video game from 2009 since many fans consider it to be canon, including myself. They made the effort to basically remake the game for current-gen consoles, so it wouldn't surprise me if there was a passing reference to the events in that game.