He sees Randy dragging Tanya outside the tower and instantly charges while shooting. It's so far away he can't really aim well so he is risking shooting Tanya (their only real medic) at the chance to kill Randy. In his own journal he says it was blind luck that he hit Randy at all but was only able to get him in the arm.

After spotting Randy on their cameras he instantly drops everything to go chasing after Randy. Once Michael sees him in the alley he opens fire and them gives chase when Randy runs. He bails on Puck after getting a boost over the fence so he can keep chasing Randy. He wants Randy dead for sure, and at any cost it seems.

He doesn't even chase after Ink in that same manner.