The more obvious way is to avoid Joseph Bonaparte to emigrate to Haiti at the first place.
Joseph Bonaparte, a man who dedicated his life as abolitionist, is arguably having equal, if not more important long lasting influence despite of his less flashy life as a Colonial Lawyer working at first to promote emancipation of African Slaves, and later on working with Jean Jacques Dessalines to manage the newly-independent nation-state.
Of course when his brother seized power at France, The Haitian council agreed to give Joseph Bonaparte Imperial Crown of Haiti to become equal to France, at least in theory. Him marrying Dessalines' daughter might be a factor in this too...