/loot kill does not drop Player-kill only drops when executed by tamed Wolf

How to reproduce:

1. Summon a tamed Wolf
2. Summon a mob to be killed
3. Run the following command on repeat:

/execute as <Wolf's UUID> run loot spawn ~ ~ ~ kill <Mob's UUID>

 4. Observe as no player-kill only drops are generated, even though they are when a tamed wolf actually kills a mob.