If you keep him alive all the way to the elevator. He will stay behind and defend the position. While u and Justus go down the elevator. The shooting stops with explosions. He's dead.
I know this is over a year old, but yeah, no WAY is he alive! and like @Fortu said, he can't take 30 VC9s to the skull, And even if he could, one of 'em would hit the tanks on his back!