You are in luck, as far as looking for descendants of the Dugas family in Haiti. We are among hundredths. The Dugas family was one of the most prominent and prolific family of Saint Domingue during the entire colonial era. Regrettably none of the descendants and offsprings bore the surname Dugas.
The Last Dugas of Saint Domingue took refuge on the Atlantic Coast of the united States during the evacuation of the island. Members of this family became planters in Augusta Georgia and other parts of that state. Indeed they were related to the Rossignol Lachicotte Desdunes of the Artibonite valley.
Elisabeth Adrienne Dugas married Paul Rossignol La Chicotte de Belleanse in Augusta in 1821 ( He was the son of Louis Rossignol Lachicotte de Belleanse and of Madelaine Elisabeth EmilieRossignol de Grandmont, his second cousin). A brother of Elizabeth Adrienne; Louis Frederick Dugas was also a planter in Augusta. I fail to remember the metropolitan origin of the family. I will soon send you more precise information.