I'm on the third floor of the Nashville Facility early in the main quest. There's this guy named Charles Quixote in the Conference Hall who is in a Servosuit. He won't take fatigue damage from any source I'm capable of inflicting. Heat Sink says "Impossible to Hit" and won't let me use it on him. The taser sometimes knocks him out, but never does fatigue damage. The sleep grenade and sleep spray have no effect on him. I thought it might be because he's in a servosuit, but the sleep grenades work on me in my servosuit. Any ideas on why this is? Is this a bug? Any suggestions on how to knock him out? Or any way to get him out of the servosuit? Thanks!

EDIT: I just used console commands to cheat, and he's immune to Karate Chop and Wear Down, too. I think this is probably a bug...