You are correct that there is more than one species of Chromis in the Caribbean. I was wrong. But I wouldn't say there are plenty of them. Of the 86 species of Chromis only 3 are found in the Caribbean. Chromis cyanea, Chromis multilineata, and Chromis insolata (Sunshine fish). The one I am most familiar with is the Blue Reef Chromis (Chromis cyanea). The first two are very common reef fish but none of them have any orange coloration. This isn't unusual as the Atlantic ocean is much younger and smaller geologically than the Pacific and while there are representatives of most fish families in both oceans there isn't the diversity of species in the Atlantic like you have in the Pacific.
Only Chromis cyanea is actually found in the trade.
Regardless, the fin shape and head to body length ratio do not match Chromis.
Andy