Verified answer

It's that STUPID AMERIKAN THING of thinking they have to say ANY WORD ending with an "A" or an "O" by saying it with a little laugh. Amerikans HATE MEXICANS but they have picked up a SPANISH way of pronouncing words and they are too STUPID to realize it.

the accents between st. thomas/st. john and st. croix have some differences, so it is not so simple as to try to make it a cut-and-dried imitation based on a limited exposure. likely you should leave it alone if you are not sure, there are no real pointers to offer. that would be like asking how to write any accent you hear anyplace in the world. you have to hear the usage, context, and meanings. to the acclimated ear, it sounds nothing like jamaican. each caribbean island has its own sound expression.

I can only say that when I was on St Croix last year, the locals sounded like Jamaicans. They also wore dreads.

Go there and listen to the locals.