Keep in mind, they didn't show him dead. They showed him dying. Nick is just inside, there's still the possibility that he can come out call the medics. People have been shot in the neck and lived.
Think about that, he lives. Then the big sheriff-like dude starts scrambling to off have him off again. That would make a good story line as well.
If you think that to much of a stretch, remember Delco on CSI Miami got shot in the head and then return to work after a few months.