That seems to fit the evidence cones up on the berm in the grass and clustered outside the parking lot. Very likely those were not brass form rounds fired by bikers, but sniper brass. (Too far for the average handgunner.)
That’s how I read it.
Sniper brass. In my hypothesis, fired by the SWAT snipers on over watch at the Cossacks who were shoving the U/C biker/cop out the door onto the parking lot.