Guild Wars 2

I’ve basically farmed blackgate invaders for last few days and I have yet to receive ambient creature killer credit.

It baffels me because don’t ambient creatures roam in large groups for protection, due to lack of killing power?
Ambient creatures run when they see a threat no matter how small, no?
Don’t ambient creatures get one shotted within the game?

Anyone else have this issue on their borderlands?

side note They do drop exceptional loot and bags.

This is pretty obnoxious.