Certain drones have the ability to neutralize an enemy.
It doesn't make too much sense of a sniper round taking him out. His head would have seen much more damage and there would have been a spray of blood and pieces of his skull in a fan pattern - rather than a stream going straight down the channel he was laying in, with all other channels clean.
“There’s video footage from a couple days ago showing what looks very clearly to be a drone flying by during the gun shots.”
Are you referring to the one that shows an airplane headed to the regional airport?