The Spanish government was assisting the Archivo General de la Nación in digitalizing its archives in addition to offering copies of Dominican related archives at the Real Archivos de Indias in Seville (covers the period from the arrival of Columbus in 1492 to the departure of the Spanish government in 1865. Only documents and books during Spanish rule, so nothing from The French Era or the Haitian Domination or during the times it was a republic.
I have no idea the status of that, just that it greatly predates the current action by the city government of Santiago.
The Mormons digitized many Dominican historical documents, mostly birth, baptism, marriage, and death books kept by the Catholic Church. They also digitilized the slaves book regarding birth, baptism, marriage, and death books. Since the Catholic Church was the only one that kept such records, descendants of slaves in former Spanish colonies have this additional source for genealogical research that doesn't exist in countries that were British colonies.
In the case of the USA, huge swath were part of Spain but slavery wasn't huge there compared to British places such as Georgia, South Carolina, Alabama, etc. Despite that, places like California, New Mexico, Texas; Florida, etc should have those books too and it's probably available and digitized by the Mormon's. That would be useless for the vast majority of American slave descendants though, since as previously said there is harfly a paper trail for the descendants of slaves of the English and later Americans.