Co-op Campaign is something that would need to be planned from the very start of a game and is very hard to do an any console.
This is mainly because in almost all engines, regions are used to stream in areas of a level. On the same TV with 2 people, it poses a challenge when 2 people stray far apart and it has to load 2 different parts of the level doubling the amount of memory required. It can be done and has been done in the past, but based on our team size and time, we decided early on to give polished and fun as heck co-op modes rather then campaign. (where 1 person would always miss half the cool cinema stuff anyway in the level because that are away when the other player triggers it)