It's happened to me twice now. If I get feared out of combat, when I reinitialize combat with punishers in Avalon Dunes, one of the punishers won't die at 0 HP but goes negative. One time, it did die at about -25k HP. The other time, I crashed, getting a message to the effect that the punisher tried to die twice.
Just their way to punish you…See what I did there? Lol. =P
Fatal: "Something terrible has happened and has made Punisher die twice! script 40101, ip 0xd0".
Happened after killing one Punisher and being feared out of combat and instigating combat again. Dead one got dragged around by live one, live one went into negative hp but eventually died. Couldn't attack the one laying on the ground, but could guard. Guarding caused more damage to Punisher, pushing her to about negative 18k hp, eventually causing the fatal error above.