There really is no fixing it either, beyond some major eugenics. We could be charitable and say what is needed is for more intelligent people to colonize the country and interbreed with the locals, since IQ of a child is highly correlated to the IQ of the parents. But for one thing, who would WANT to move to Haiti in search of fame and fortune, and for another what Western country would do so?
My idle conspiracy brain theory is the reason Haitians are suddenly being imported all over western countries is the powers that be have decided to depopulate the country and spread the retardation around. A sort of "Woke" ethnic cleansing where the people aren't put into camps and gassed, but instead thrown into the seething mass of the global population to (hopefully) dissipate and be absorbed.