https://the303.org/tutorials/gold_qc.htm#A1
"Event ID 1000" is an animation event that can be called on a specific frame in an animation to "kill" the monster playing the animation. Animation events can only be triggered within a model's animation, which means that if you wanted to use this method you'd need to decompile your model and add the event somewhere at a specific frame.
$sequence fire "turret_shoot1" fps 150 loop {
{ event 5001 0 "51" } { event 5001 10 "51" } { event 5001 20 "51" }
// { event 5001 5 "1" } { event 5001 15 "1" } { event 5001 25 "1" }
}
In this example, "event 5001" triggers a muzzleflash to appear at a specific attachment, with the number right after the event dictating which frame of the animation the muzzleflash appears. To kill a monster with an animation, you'd use event 1000 and then add the number of the frame you want it to actually die right after. However, this method would require decompiling the Shock Trooper's model and either adding the event into the animation you want to use or adding a new death animation entirely.
That being said, I'm not entirely sure what other methods there are. The only examples of a scripted sequence in Half-Life that ends with the NPC dying that I can think of are the dying security guard in Office Complex and the dying scientist in Blast Pit, both of which kill off the monster through Event ID 1000.