We plan to re-take the class/CW here and finish our OW dives in warm, caribbean waters, possibly this fall.
Good to hear that you are still going to pursue certification. I also remember your original post, and believed (and posted as such) that you unfortunately linked up with a poor operation for your initial OW class; no good way for you to know that in advance, it just turned out that way.
I trust that you are going to do the academics / CW with another / different shop in the Charlotte area this time, at least one that does training in an enclosed pool area. As for what you can learn from the thread you pasted into your post:
I recently found this thread on another forum and wanted to get opinions from you wise SB members. ... What can I learn from this story (or what can you offer) to help us pick a better shop to finish our OW certifications with?
As several posters have mentioned, the critical issue to is estanblish clear communication with the dive op so that they understand what you expect, and are prepared to provide the service(s) you want. I do not feel a great deal on sympathy for the poster in the thread you referenced - he had what seems to me to be an unrealistic expectation of the type of support a charter operation typically provides, and what the duties of the DM are.
In your case, you will be completing your Open Water dives with a Caribbean operation. Are you planning to pick the operation, or are you looking for advice from SB posters? There is nothing wrong with you picking the operation, just be sure to communicate clearly what you want - open water dives to complete your certification - and make sure that you know what paperwork you will need to bring (DO NOT simply reply on the shop in the states to know what the Caribbean operation may want). MOST DEFINITELY, speak with someone in authority at the Caribbean operation before you get there. A good operation will be happy to speak with you, and answer your questions. If you decide on an operation, and then have difficulty getting them on the phone, or they say, 'Just come here when you arrive, we will work out the details then', stay away from them!
Once you have picked an operation, post on SB and ask for feedback from SB members who may have used them, eiothert for OW certification dives or for charters.
Finally, going back to the experience described in the thread you put in your OP, you should plan / expect / intend to become independent divers as soon as you are certified, beginning with the first post-certification dive. Do not start out by relying on a DM to shepard you through a dive. If a diver cannot assemble their own gear by the time they complete OW certification, if a diver cannot listen to a competent dive briefing on a boat and then safely enter the water, complete a simple recreational dive within appropriate limites of depth, time and gas supply, and then exit, then there was a problem with the certification. I doubt there will be any problem for you, by the way, just making a general point. There is something to be said for diving with a local dive professional the first time you visit a new area. There are some dive operations in the Caribbean who offer DM-escorted dives as a routine. But, in those cases, the DM happens to be in the water to point out interesting sights and sites that you might otherwise miss, not to check you air, not to supervise your dive, not to assemble your gear, etc. Don't rely on a DM to 'get you through' a dive.
Also please post again after you finish the OW dives this Fall, to let us know how things went.