We were married at CTI over Thanksgiving last year (and are actually booked for Negril next Thanksgiving, so maybe we will see you there!). On Thanksgiving we elected to eat at one of the fancier restaurants to give it a "special" feel (Eight Rivers at CTI), they had a great Thanksgiving dish that my husband had (sort of a fancy/Jamaican take on turkey with stuffing, potatoes, etc.). They had special menus with the Thanksgiving meals listed (and the normal menu, too). He was super excited to have turkey!
We were at CN last year at Thanksgiving and ate at Otaheite on Thanksgiving (wasn't chosen for that reason, that just happened to be the day we got the reservation). Food was great. I don't remember a lot of US Thanksgiving type foods on the menu but that is a US holiday and not a Jamaican one. No matter.......food is great no matter what they serve.