Where are your sources for this claim? From what I've read DR and Haiti where about even until the 1950s when our economy started to surpass theirs. I don't think there was ever a point in history where the average Haitian could look down on us for being backwards compared to them, and definitely not during the Trujillo era. The Parsley Massacre happened in 1930s in the early years of Trujillo's regime, and the Haitian goverment was practically crying to the US government for compensation from DR. If they where so powerful during this time they would have done something about these killings instead of whining to the international community like a bunch of cowards. I'm not just talking about military interventions either, they could have placed some sanctions if they really had the economic advantage, but they didn't. Again, the DR was never "backwards" compared to Haiti. Less populated, yes, but definitely not less developed; not even when their side was the "pearl of the antilles" under the French, since Haiti was entirely an exploitation colony with little infrastructure and architectural development, just compare Haiti's colonial sites to the ones in DR.
Actually his claim are indeed correct. During the beginning of the Trujillo era, Haiti was economically better off than her sister nation Dominican Republic. This was another reason why Trujillo ordered the massacre of Haitians and darker hue Dominicans. He was concerned after visiting the border region that Haitian nationals controlled the commerce and the Haitian gourde was preferred currency as it was stronger than the DOP.
It is well known that the president of Haiti during the time Stenio Vincent and Trujillo were allies and did everything to solidify control of their respective country. It is also important to emphasize that the USA divide and conquer geopolitics had an intricate role in how things were handled. It is also rumored that the two were cousins via Trujillo's Haitian family tree "Les Chevaliers"
To chime in on the territorial encroachment of Haitians in Pedernales is absurd. It's as if saying the anglophone Canadians will decimate francophone Canada.
Right now Haitians should continue building bridges with her neighbor DR for Haiti to become self sufficient and deter Haitian nationals from crossing the border for a better future. It is up to Haitians and Dominicans to reconcile and live respectfully in each nation in harmony. If the French and Germans are allies and partners why can't the two nations who've been exploited by all colonial power then American imperialism can't have the same relations. Haiti needs to stop allowing NGO's to defame DR in the international sphere and DR needs to continue controlling her borders albeit respecting the Human Rights of the Haitian nationals.