The only violent vengeance that would help is Putin being hung on a gas station railing.

I highly doubt that. Russia is mostly rotten to the core, there are too many for way too long in line with Putin. After him there would be another one and most of the people will continue to support these atrocities.

Also the Band was Piknik, quite the supportive band of the russian government so I assume most of their fans are also part of this group. Still civilians though…