Don't believe all the BS you hear online. This is apparently the first video,
https://twitter.com/stillgray/status...85918303580162
I can't really see what's going on, but the story is that the guy who got shot rushed him blindside, the 17 year old turned and shot... That's the kind of thing that happens if you rush an armed man in a riot. Freeze it at 51 s, you'll see, that's no "perfect head shot", the guy still has a face. 2 inches higher or to the left it's a miss.
and this is the second
https://twitter.com/i/status/1298520602630688768
That's pretty clear self defense - those guys were mobbing him, and he could reasonably expect to get beaten to death...