No. You have to play the COOP MP portions to alter the Readiness status. There is no way around it. If you don't play the COOP missions, you're ending is going to be abysmal. I'd like a trainer option that could alter it.
It irks me to no end that they force you into playing a aspect of the game you shouldn't have too.
[Edited by marines0811, 3/7/2012 5:39:04 PM]