For countries closest to Sint Maarten, you omitted Sint Eustatius (Statia), Netherlands, and Saint Bartholemy (St. Barts) France, which are both closer than Dominica or Antigua and Barbuda.
I didn't realize you expected the "country" name rather than the country name for the ones in red when they belonged to the same country (e.g. "Faroe Islands" as an answer for Greenland). Makes sense in hindsight, I guess...
Minor points: 'UK' not working for 'United Kingdom' and under 'Curacao' Aruba is listed before Bonaire despite being 77km away instead of 41