It's hard to believe any of it as the true reality after reading how much this article differed from the new Netflix documentary A Gorilla Story: Told by David Attenborough that I watched a couple of weeks ago. The story they told involving these specific gorillas was quite bit different than the one described here.

The aggression could be from trauma, but aggressionn is also just part of being a male gorilla. They need to drive off rival males and, if they dont have a troop, depose or at least survive an encounter with a full silverback. Aggression is a useful tool in such situations.