Heres my take on what I think goes on in this enclave.

I have two theories:

Theory one:

You know how the cub is basically "Erased" From the game?
What I think happens is they kill the cubs. But why do they only accept one specific marking at a time?
Maybe the enclave is racist. They are not. What I think is happening is they skin the cubs before death. Yes. I think that the gorilla enclave is like a black market. After your cub is "Erased" Its pelt is sold for beetles. But why a specific trait? I think orders are placed where the customer will ask for a certain marking on the pelt. It all makes sense now. But why under a year old? Its because cubs are more gullible then adolescents. They don't know whats coming.

And the less gruesome theory 2:

The gorilla enclave is a sanctuary for unwanted cubs. All the cubs are well fed, trained, and nurtured. They will release the cubs into the wild after a year to either start their own pride (Male) Or Claimed by a handsome king to be part of a pride (Females). The problem with this one though as it does not explain the fact that the quests require a certain marking or color.

Anyways, Hope you have fun on lioden :)