Very strange. When i played previously(blood mage) in a cave where is located goblin brother i beat bear and he didn't appear(got quest but he still didn't appeared though i didn't even knew that he should be there). This playthrough as a rogue he jumped out right after i beat bear. Didn't had quest this time.
On unrelated note. If black goat symbolize "Mother" than who is woman breastfeeding child which we meet everywhere(even underground pub). I honestly thought it was her, keeping eye on things.
can't be hundred present sure about the cave encounter whit what i think you meant Kobold, considering the bear can be encountered in different part of the cave from what i remember whit it wandering around, you probably somehow got the encounter a bit outside the trigger range or something.
i also have noticed that you sometimes are able to somehow bypass "Trigger" locations fore story encounters like the bear fight whit Hanna and Kaliska, or that they somehow get delayed or something.
as fore the unrelated note, they meit just both represent "Mother" considering the goats only show up if you are insane, wile i think the nursing one show up regardless of insanity, to be honest i personally didn't really think much on the fact that an nursing mother ware around the please other then whishing to have had some dialogue whit some of the once around, they ware alvei's short of strangely silent whit little interactions compared to other characters i guess, but if they represent "Mother" then that's explains a lot.