I found an article from 2020 that has nothing to do with Haiti but does say the following about Level 4 travel advisories that were in effect because of COVID:
Most travel medical insurance plans will exclude any coverage if you enter into a Level Four Advisory Country,” says P.K. Rao, president of INF Visitor Insurance. Since all countries are currently categorized at Level 4, that makes crossing any international border a risk, but it depends on your plan. For some plans, Jeremy Murchland, president of Seven Corners insurance says, “It's possible the Level 4 travel advisory may affect only specific benefits,” such as not covering non-medical emergency evacuation.