Oopps... I screwed up. How to repair an improperly exposed white backgrou

[objektiv]

I did an entire shoot yesterday without realizing that one of my back lights was not set to slave. DOH! I hate to "fake" things in photoshop but I *really* need to salvage a few of these shots. What i've got on one side of the frame is a nicely exposed pure white paper backdrop and other side fading into a cream or almost yellowish colored off white. I'm wondering what the easiest method to fix this while producing usable results (or as close as I can get). I have repaired something similar with painstaking use of the paint bucket but it becomes extremely painful when you have to edit the area right next to outline of the models body. I'm hoping someone here has a good method for repairing this. Other than this one major screwup the photos are pretty much ok and exposed properly.

One other bonus, I took all the pictures in Nikon RAW (D70). I don't know if that might help or not.

Thanks.