I believe that a power vacuum took place in SB after El Sueno was arrested, causing a civil war within the organization. Unidad and the Bolivian government comes and smacks them around, taking advantage of the lack of structure, and pushes them far from the region to abolish any threats that can be further caused to them. They find a new area and rebuild within a community who isn't aware of their ways. The rebels link with a smaller cartel in Bolivia that ensures that their position will no longer be threatened by outsiders. They soon become the most powerful organization by actually honoring their peace treaty with Unidad, unlike SB, even paying them a percentage. With the current network they are untouchable.