Oh, I was speaking of decades earlier when the place got annexed during the Jacobin Wars.
I'd imagine in-between then and the present of 1896 that the slaves would gradually learn English and this would take an even bigger upswing come emancipation with the Clay Proclamation. It's about a century's time for them to.
Cuba, unlike Hispaniola, never fought a resistance war against the Anglo-American occupiers, which would explain why its population never got purged as a comparison.
I suppose I forgot when Hispaniola was annexed. It didn't seem to get much mention on the wiki.