The co-op in this game is Xbox Live only. So split screen isn't gonna work. Anyway, the good news is that whether you are the host of the game or the person joining, the time will count for both. The only thing is that you pretty much have to this with a friend because the "Smart Match" option fucking sucks. Seriously, I waited like 30 minutes looking for one. Don't waste your time.
Feel free to comment down below if you're looking for a partner to boost this with