Had this question pop up before and had mixed views with those I spoke with.
You cause someone to be downed but you don't hang around to see them respawn or fully die. Did they die or not?
If that person does die, they have a responsibility of following NLR but perhaps you could cross paths with someone again as such of your incident. How are they to know you died or not? NLR is written to put the responsibility of the player who died to forget enemies, but the enemies won't necessarily know to forget the player who died. As I see it's not written for other players to take into account and you couldn't necessarily say they know you've fully died and following NLR.