sorry to burst your bubble but in the 70's and 80's there was so much imported dutch genetics into jamaica that most of their strains there are of dutch/jamaican hybrid. alot of jamaican weed has skunk genes in it as skunk #1 was imported to breed with the local stuff to improve yield and hardyness of the plants.
The old Jamaican strains are still there, just much more rare.
Doubt skunk reached Jam till the late eighties, and it was only used for yield and quick flowering not hardiness, as it was not as mold or storm resistant as the old Jam strains. Also some of the real Jamaican strains are named after skunk such as "purple skunk" which has no actual skunk in it.