Define Minecraft death as kill?

I'm currently programming BedWars and I'm at DeathEvent right now

It's supposed to be that when you get hit in the void, then the one who struck gets the kill.

But now, the one who hits him into the void does not get the kill, and so it is considered a normal "death".

I ask him in my current code if the killer is zero. If not, then it should be considered a kill.

Here's the DeathListener:

Do not know me with all the possible events that exist at Spigot, but actually there should be one which comes into play, if a player is beaten. You could always get the player from whom someone else was last hit, and if someone died from the void, simply assign that kill to the player you had previously saved on the last hit.

Yes, yes, thanks