RE: How will we kill this bird now?
2 questions...
1) Was he suspicious before your buddy shot? If he was, and he spooked bad, I'd leave him alone for at least a week, then hunt him from a different direction.
I took a shot a couple of weeks ago that I shouldn't have taken. The bird spooked bad and I didn't hear him the next 2 days. I went back a week later, comming at him from the back side and he nearly knocked my decoy over.
2) Did he see you move?
When I got that bird, he had a buddy with him. His buddy stuck around after the shot. I tried to wait him out so I could hunt him the next day. He busted me after a while and I don't expect to get another chance at him the rest of this season.
I had another pair come in on me a couple of years ago and I killed the lead bird. I hit him hard, but he was flopping and moving away from me, so I had to go stand on him. That spooked the other bird (he was a piebald) and I haven't seen him since.
My conclusion is that if he sees you move after a shot, he's done for a while. I'm not sure how thick the birds are in North Carolina, but I have the great fortune of hunting in Mississippi, where we have close to half a million birds. I can always go and find another one. Killing him is a different matter altogether, though.
Change locations, maybe change calls and decoys and wait a week, then try him again.
Good luck!