Raz counts as an allied character. Unlike, say, Interlude 1, where every unit is a "fake" copy with preset stats and equipment, this is your actual Raz with scripting on top to make him unselectable. Raz starts inside the zone that we need to reach, so we have to get him out and then back in. Thus the first shot is to get him out of the area, and the other to make him cross back in. It is theoretically possible to do it in one shot, that requires Riley hitting Raz just right so that his ragdoll ends up between trooper and sandbags in an illegal spot that teleports Raz back into the area when looking for a respawn position, but that's nigh impossible to achieve on purpose.