What about the fact that when another eyewitness told police that the kid was the one screaming for help, the police officer corrected her and said something to the effect of, "no that's not what happened Zimmerman was the one screaming for help". Conveniently ignoring that one are we? What about the fact that its standard procedure to do a tox screen on anyone who is found in the same situation as Zimmerman, something that was not done? But yes clearly you have all the facts and the police acted properly and didn't do anything that wasn't following standard procedure in this case.
Of course I don't know what actually happened, but neither do you. What I do know is that the eyewitness testimony you cite to is not the only eyewitness testimony that was provided to police, and that police did not follow proper protocol in this case. I was offering one theory on what happened, something that is more plausible to me than what you suggest happened. Which is a guy saw someone walking, got nervous called the police and then against the advice of the dispatcher following the guy and then something happened and then the guy who was followed attacked the follower, the follower then shot the guy who was followed. One has to wonder what Zimmerman would have had to have said to the kid to get him to attack a random guy who walked up to him.