Yes, that’s the original joke - having been taught in British schools, they learned about Nicaragua and Costa Rica.
Why this is in the school curriculum, however, is another matter, and this thread is pointing out the coincidence that the British empire colonised Nicaragua for like two centuries.
Well, not “kind” of dark, but really dark. I mean, the cartoon couldn’t be more direct in comparing the “haitian Simpsons” to the jews and other racial minorities in Nazi Germany, with the last panel being a page from the life of Anne Frank.