Bug in version 3.6.1
Vagabond's trigger is being weird, I beat the bear a bunch of times and he just wouldn't show up(the bear re-spawned every time I left the cave), I tried saving outside the cave, shutting down the game and reloading a couple of times, leaving the forest and coming back, nothing worked...
But then weirdly enough, when I loaded from a save inside the empty cave, already beat the bear before saving, vagabond randomly decided to show up, the quest log didn't update so I assumed it must've just been a fluke and didn't register but when I left and came back inside the bear didn't respawned so I figured, it either worked or I kill Ostom, I'm not going to keep trying to get that to work, and it did, not sure what's up with Vagabond's trigger though.