Releasing the game unfinished would be the worst mistake to make. Please take your time, delay the release date until you finish the game. The reviews will not be forgiving at all. Also, playing the single-player campaign is always prior to getting into multiplayer. In addition to that, the co-op against AI is one of the major playing ways in multiplayer, if AI is not ready enough then the experience is hugely affected. You should release the game in full playable package.
Or maybe you don't care now since you got our money?:confused: