My impression from watching a couple similar videos is that the Ukrainians will land drones outside the russian bunkers in order to force them to get out to get rid of them. Once an orc gets close, they remote-detonate the drone.

Apparently this is more efficient than trying to hit the bunkers. If you know they're in there, you can just keep the drone lying in wait. As long as the russians stay inside fearing the drone, they're effective put out of action, and once they try to leave you can send them home.