Save both, plug the drive into your PS3, and copy the save from your drive, overwriting your current gamesave. Start the game, and enjoy.
I didn't want to let this out, but somebody else figured out how I did it, and told people on nextgenboard how to do it, so no harm in giving it away anymore. Hopefully it will just speed up IW's patching the issue. I told them weeks ago how it was done, and how to fix the issue. It is in their hands now.
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