I Saw The clip and Wow! a hard one… I can only imagine playing with the screen gain, clip black, clip white, etc… but remember keylight is very powerfull and when you select the color it keys almost every shade of green, maby try using also Color KEY to se what happens, (i dont have AE installd in this pc so i cant do it right now) I personally think that the best would be re-shooting :S if people wears green using a blue screen… and remember always telling people to bring clothes in other colors rather than green.
I’ll try to do it, if I come out with something I make you know!