They had a plan to shoot and escape, but I don't think he blended in with the crowd that I know of. I think they said he went through a neighborhood before dumping the rifle in a wooded area.
But the fact he didn't wait around was telling. Professionals will verify their shot placement and kill. It's not like movies or video games where the scope stays on target through the whole shot. A .30-06 produces enough recoil in a hunting rifle that the scope will be well off target after the shot. Professionals can dial back in quickly and evaluate. Amateurs not so much. Regardless, the shooter likely would not have known shot placement except to know CK was hit. I'll give that a 50-50 chance though. Kirk dropped to the ground but it was just barely long enough to know you hit. But I don't think the shooter stuck around that long.
The crazy thing is nobody noticed him running off with a rifle? Even in a case or wrapped in a blanket, that's gonna look suspicious. But I'm the chaos, anything is possible.