I mean, he's not the one taking great pains to defend an attempted murderer on an online politics forum, so ¯\_(ツ)_/¯
Here's a video of the shooting.
https://vid.me/V3JL
Now its quite fast moving so its difficult to see every detail but it looks very much to me as though the shooter (in the yellow hat) was being assaulted by antifa at the point of the shooting. Which would fit in with the shooter's account of what happened and which would make the shooting self defense not attempted murder as you claim.
I've watched it several times now. There is scuffle left of center that kind of moves to the center, yellow hat is NOT involved in this. He starts to move towards the scuffle like a lot of the crowd. At this point a large, short haired man moves at least 10 feet (if not twice that, hard to tell, the earliest I can find big guy is maybe 10 seconds before where he is standing behind a man with brown hat right after the camera pans left and stops) and intentionally slams into yellow hat and a small melee ensues. I think there are some yellow hat friends around, but it also looks like there is another person or two in the mix on the big guys side. This is when yellow hat shoots.
Yellow hat better not get charged with anything. He probably shouldn't have brought a gun, if he was worried for his safety he should probably just stay home. But we live in a free country and he was in public minding his own business when an asshole violently assaulted him, he should (and does) have a right to defend himself.