Sony and Microsoft have requirements to track which players are present when trophy/achievement events are started (to prevent achievement 'abuse' of joining at the end of something and letting the host complete it). Since the game wasn't designed to even track which character was present, for the most part, if could not for players, so can not give achievements to players that are not host (or player 1 for local co-op). That said, I've seen some people saying both did get achievements on console.
