His egress could involve little more than putting his rifle down and moving a few feet away. The fact that the photographer in the car knew the target suggests a DC type sniper. Juba may be in the trunk.
Perhaps even a smallish squad to provide security for him. One might not think to look for a sniper in the middle of a knot of 'locals' who are presenting themselves as a smallish group.
Scarey thing is...he's not doing anything but following regular sniper doctrine as far as I understand it. Are we really *that* dependent on the other side being morons to catch them?