See post #166 where one witness says he was standing (with his wife) about 7 or 8 feet away... that isn’t a lot of room-for-error & depending on how things were lined-up the effective angle-difference from [from the shooter’s perspective] between the ‘target’ and the ‘bystanders’ could have been quite small.
Assume for argument sake that they killed two people, the intended target of their volleys, and some kid who was just in the wrong place. I think both are voluntary manslaughter.
I'm not saying a second degree murder charge is off the scale, just that I don't see a jury finding the sort of "indifference" that is connoted by murder.