FWIW, when I was talking to the homeless guy the day that I drove over to that location, he said that he recalled the locals talking about two kids from a different neighborhood who were shot for trash-talking.
But who's to say whether he was telling the truth, or if maybe he was talking about a different incident.
I live in an area that has a large homeless population. In fact there are several homeless shelters and outreach christian organizations in my neighborhood. As someone who comes from a rural background in another state and now lives in a city it has always amazed me how much the homeless people in my neighborhood notice my actions. They always talk to me, never ask for money and if my routine changes they notice. If they havn't seen me around in awhile some will come up and hug me (mind you I work for LE). I gave up one of my dogs in October (to someone that could provide him with what I thought he needed, a yard and people there for him more then twelve hours a day) and when I walked just one dog, less than two days of giving him away all the homeless people in the area came up to me asking where the other dog was. It took two to three weeks for my other neighbors that I've had for five years to do same. I've known some of these homeless people for over five years, I wouldn't be too quick to discredit what he says.