Whenever this question arises, I strongly recommend doing the water work in a warm, clear water, comfortable place if at all possible. If that means a trip - well, you then have several days after they're certified to enjoy their new accomplishment together!
I would insure that the certification process is very comfortable so the student can keep their focus on all of the new content, and not on their physical discomfort. They're being asked to learn, remember, and implement a bunch of new stuff in an "alien" (at first) environment. Why not remove as many obstacles as possible to help insure a super positive outcome? They can add layers of complexity later (such as cold water and its equipment, currents, etc.).
I say this because my wife got certified in North Idaho (where we lived then). We had waterfront property and our lake would reach 80F in the summer. But the classes were held in Lake Couer d'Alene which never really gets warm and has a strong thermocline at ~25 feet below which the temperature was frigid. They stuffed my newbie wife into a heavy 5? mm wetsuit complete with gloves and hood, got her good and cold, and then asked her to unclip her various BCD buckles, reattach her weight belt, etc. She couldn't feel anything through the gloves, was chilled to the bone, and when it was over she drove home in tears.
I could see our future dive vacations disappearing before my eyes as I rode silently in the passenger seat. She was embarrassed, felt like she was failing me and my beloved hobby, etc. My wife has a very strong personality and nothing much gets her down but that experience was awful.
She didn't go back to her open water completion for half a year, and even then it was chilly at depth. She skipped the gloves so she could feel things, passed just fine, and when she got out of the water I told her "I will never again ask you to dive anywhere that requires a wetsuit unless it's your choice".
She's now a full-blown convert, has her AOW, has 100+ dives on her Perdix and more in her paper log from before we had dive computers. We literally just got back from a week on Bonaire and a week on Curaçao. She's a super enthusiastic diver, but it was a close call after that Michelin-Man wetsuit and cold water experience.
With all of that in mind, if you're looking remote I'd recommend Buddy Dive on Bonaire for a really good instructional program (but it has less "night life"), any of the good LDS's on Roatan West End (touristy evening activities), or one of the good shops on Curaçao's west coast (a larger island with lots of choices for post-diving action).
After completing the E-learning stuff at home, my brother in law did his wet work at Buddy Dive with us on this trip and was extremely pleased. There's a lot to be said for on-water accommodations, schooling, equipment, etc. If after-diving activities are a higher priority then I'd probably favor an AirBNB on Curaçao and a shop like Go West (north) or Ocean Encounters (south). You could also stay at LionsDive, which is where Ocean Encounters is based, and thus get the benefit of "on-site everything".
Hope this helps, and congrats on another diving family member!
