Vile Deathroach

Found one Rare as main pet at 56.12, 71.56, also had rare Clinging remains as secondary which was unfortunate, but that roach has priority

Found one at 58.3' 78.6 as a primary (HP)...took about 15n minutes.

I spent around 2 hours battling every pet all along the roads in the Beastwarrens, finally found one. Too rare to be picky on its quality. So I grabbed the poor and stoned to rare

Finally dropped right at the entrance to Korthia. I also like others below had to run around and do a few pet battles for about 30 mins till I saw him spawn. He actually was the spawn he wasn't a backline pet.

51.81, 85.3 Fronttline pet

Had to run around doing pet battles for about 40 mins to make some respawns around the Beastwarrens area before this showed up.

I'm running circles in outer main pathway through beastwarrens, theres like 5 wild pets, using Xu-Fu to kill first critter, forfeit - that will forcespawn a new one. When I get up northeast, I poke my head into elite area, and kill the single helsworn soulseeker which can drop a pet too. 

I use the kill every wild battle pet strategy to spawn this.  With patch 9.1 protecting battle pet from being aoe to death, you literally have to go into pet battle to kill them.

Found one as the main wild pet at 45.45, 65.35. I have been searching for days for one as a primary or secondary.

These rare guys share a spawn with the other two pets in the Beastwarrens. Kill every battlepet that you find until one of these things finally spawns in. It will be the primary pet, not backline.