Haiti government and police are outgunned, under siege 24/7 and barely able to fend for themselves, never mind providing security in Labadee. Although I am speculating here, I won't be surprised RCCL and the local gang controlling the area may have some sort of behind the scene arrangement to leave Labadee alone in exchange for economic or monetary benefits aka protection money. This is usually how businesses are done in the third world where central government is dysfunctional, leaving local armed gang or warlord to become the de facto ruler in the area they control.