What is a non-lethal kill?

In We Happy Few, the player's journal contains a statistics page. One of the stats is called "Total non-lethal kills".

Putting aside the blatantly self-contradictory nature of that label, what is considered a "non-lethal kill" by the game? Is it just any action taken by the player that renders an NPC unconscious rather than dead? (Directly causing a death counts as "murder"; indirectly causing a death does not count toward any stat.)

Initially, I assumed the word "kill" was simply an artifact of the fact that in some games — including Dishonored, and BioShock Infinite: Burial at Sea - Episode 2 — a non-lethal elimination is functionally equivalent to a kill, with the only differences being that a weapon or move designated as "non-lethal" is used and the NPC's state is "unconscious", not "dead". For example, in BaS - Episode 2, unconscious NPCs never wake up and their bodies can even despawn, just like dead NPCs. This is also the case with every Dishonored game.

But, while playing We Happy Few, I just came across this in-game tip:

Unconscious people eventually wake up and walk away when you're not looking.

... so I guess that theory is out the window, basically, since you could technically "non-lethally kill" someone twice. Does that also mean they die, non-lethally, twice? (This may sound like an absurd question but answering it in terms of "killing" someone twice would certainly help with answering the primary question.)