Only succes i have had saving beetle infested trees was with malathion. I get up in the tree with a gallon jug of malathion and pour it between the fronds and truck every frond and it gets into the hole the beetles make. If it dies be prepared to kill the beetles by hand when it comes down.
Instead of cutting and leaving a stump you can spend about an hour or so and dig all around and under the root ball and the weight of the tree will pull out the root ball then you cut it up and fill the hole but no stump left.

Best example of Malaysian Dwarfs are what you see in Chetumal and they are resistant to L. Y. but dont grow tall and the nut has no meat only water.
The most common hybrid is the Maypan which is bred by crossing the Malaysian Dwarf and the Panama Tall. That is what forestry sells I believe. It is a hybrid so it does not reproduce itself only one of the parents. Each hybrid must be cross pollenated by hand.

Central farm in Cayo..BAHIA..email them pics of your trees..our dwarf coconut trees got yellowing, They are not immune to the disease, only resistant, one died we saved a few by drilling holes 6 inches into the trees and injecting them with tetrocycline(sp?) every 4 days for about a month, they are great help and very nice folks. They will diagnoise the problem if images you send are able to show what the problem is.

I think rotten conch trumps coconut beetle stink.
How's that for a hijack.
:-)

Back on topic - I ordered the product from tree-save and it works. There is one technical issue though - the delivery sleeve is a modified shot-gun shell and a shipment of such items can cause customs great concern.

Dianes suggestion works very well against the beetles. We've used the product Tree Saver and managed to save all of our trees but one. Merp Inc. dba Tree Saver 17894 73 CT. N Loxahatchee Fl. 33470 (561) 655-6940
In order to get around the shell issue we drilled holes as specified in the directions that came with the syringe and solution, inserted short pieces of bamboo into the holes, sealed the outer end with silicone and injected through the dried silicone.
The reason for the sealant is to prevent the product from leaking back out of the tree. The solution is oxytetracycline Hydrochloride. I would imagine if you preferred you could also use brass or stainless tubing from one of the hardware stores.
I would also contact the company to get accurate dimensions for the shell material.
This worked reasonably well, maybe not as well as the shells, but it worked. Very Very important not to use the coconuts after treatment or allow anyone else to.

The good thing about coconut trees is that they grow very fast and are cheap. Removal of a diseased tree is best, otherwise it will become a vector for other pests and infections. Pouring a gallon of poison, there by eliminating ever using the fruit, will also poison the ground water beneath it. Plant a resistant variety, remove a tree at any signs of the beetle or infection (or you will loose more) and enjoy the trees while they last.
Remember coconuts are not native to the Caribbean, so they will also suffer more disease and pest then native palms and can pass sickness to the native species. The only animals benefiting from the coconut food growing on these shores are humans and some beetles that carry a virus. We on average loose five trees a year due to storms or disease, replant ten and cut down ones we don't like how they turned out. Keeps things interesting.

Here's the hubby ( Capt. Coconut) replanting with our potlicker.

Yes that is the truth chica blanca. Plant at least 2 for each one you lose and remember that if you plant them in front of your window you will have a period of 2 or 3 years when you will have no view - well a view of the tree fronds.