I can't really speak to the rest of it but as to the the 10' aluminum dinghy
I have a 9' one with a 5hp motor
, which is the maximum rated power for the boat.
Bigger motors are heavier and drive the boat faster. This will impose additional loading on the mounts and the stern of the boat that it may be unable to take.
The stern could start to break away from the boat with all the consequences that this involves.
While a 40km trip may be doable unless my interpretation of the scale on Google earth
is incorrect you're looking at a minimum of 300 km from Haiti
to Cuba, plus whatever is necessary to get from the departure point to the arrival point.
A very rough calculation suggests that you'd need more fuel
than would fit into your boat, and if you tried to carry it the additional stress would contribute to it's probable break up.
Similar constraints would apply to using a small sailing boat. Enough food
for the long time (count in months) such a journey would take, even the shortest leg, would overload such a small boat.
The above does not even consider the effect of adverse weather, currents or winds.
I would consider it very likely that you and your dog would die of exposure, dehydration and/or starvation.
From your tone it sounds like you have been advised that you cannot take your dog with you when you leave Haiti
. While devotion to your companion is admirable risking yours and your dog's life, and the lives of those who would be asked to search for you must be considered unacceptable.
From my experience in New Guinea where expatriates often had to make such a painful decision the solution usually involves finding friend or a friend of a friend to look after the dog. It may be possible to find a local to do the same with the help of a little cash to pay for food(my recollections of this being done are vague - a family
who already have a dog may be best).