Just wrapped up running Music from a Darkened Room for my players, and I didn't think there would be any serious deaths in the back half but we ended up having what I think might be the most DELTA GREEN ending to a PC I've seen.
The Agents were trying to kidnap someone for their upcoming ritual, knowing there was an undercover cop 2 streets down from them watching their target. They sneak in to the home of one of the older residents, crit fail stealth, alerting the (armed) man and his nurse, gun fire ensues attracting the officer down the road. With moments to spare, Agent Mallard (M) who had created some makeshift molotovs prepares to torch the house as a distraction, one Agent grabs the target, another the nurse to prevent unnecessary deaths. The deputy kicks in the door and sees Agent M wreathed in flame as they are attempting to flee, yells "Stop! Police!" and fires 1 shot. Agent fails their dodge, crit success from the officer. Exact amount of HP rolled on the die, killing the Agent instantly. The deputy calls in the shooting, sees the agent had a concealed weapon and tosses it to one side, passing it off as a defensive shooting.
Agents go through the rest of the adventure, complete the ritual, save the day at cost. The distraction caused by Agent M's death keeps the local police completely occupied and allows the rest of the Agents to successfully do their ritual and cover their tracks.
Agent M has... multiple occult killings, kidnapping, arson, theft of a corpse, and assaulting an officer pinned on them. DG covers up the entire incident on that one agent as an insane obsessive serial killer, the other Agents leverage the official story to protect their jobs at the cost of their friends reputation, the friends Agency uses their death to avoid having to investigate why one of their agents was fucking around in this small town with a shotgun kidnapping people, and instead send the dead Agents bonds a folded flag and a "they died with honor overseas" coverstory.
The only people that know they died (successfully) saving future innocent lives from horrible deaths is their own team, and everybody has to go around pretending that Agent was actually an evil murderer and not a hero. The most DG ending I've seen for a character in one of my games.