I too am Cuban American from Miami, and being obsessed with ghost stories, I knew of La Llorona before HHNH did the first house in that "franchise". But what Christy says us true. Most Hispanics in Florida are from Central/South America or the islands. I'm certain La Llorona never made it to Cuban folklore, however if I do the research I'm sure there is some variant of the story somewhere among the Central/South American cultures.
With that in mind, if they do La Llorona as it was in Hollywood, Uni will need to bring the GP up to speed on the legend, or else it may become the "I Don't Get It" house of the year.