Haiti does not produce guns or ammunition. But there is no lack of either on the island.
Any entity genuinely interested in ending the misery of the Haitian people would mount a determined effort to identify the who, how, and where of the flow of guns and ammunition coming into the country. Then, they must mount a determined effort to end the influx.
If that is not one of the top priorities of any “occupying” force, then that force is illegitimate and not needed on the island.