My question was, if you don't think he followed him to continue to observe, then what do you think the reason he continued to follow him was? You are skirting that issue big time. And it sounds to me as if your are insinuating that GM followed him to shoot him.
The legal grievance process would be to just complain to the police. But that doesn't solve the exigency of that night and the reasonable belief by a neighborhood watch volunteer that an unknown and suspicious looking person might be in the community to do harm.
In addition, the police were being dispatched so why you would bring up the next prudent step would be to complain about response times etc. - that part is all lost on me. It takes LE a while to get there and someone on foot running at night can be lost easily.
As a law student I know it's not illegal to follow someone who looks suspicious to you, in your own neighborhood and to report the location of that person to the police. That's pretty much standard NW conduct.
It is also justifiable and lawful to use deadly force in self defense to prevent somone from doing great bodily harm to you.
The questions we must have answered is what caused the two to meet up physically and who started the physical altercation and where was GZ's gun...had it been drawn or was it holstered during the scuffle? These are pretty crucial facts.