In my humble opinion the flight time to the island by helicopter is not a such a big deal. It would probably take that long to get the patient and crew ready and as I said it will do no good to get them to the international airport and then take another 25 or 30 minutes getting them to the hospital. There is always a delay when you change transportation methods which also adds to the time.
Plus perhaps there are light on the runway here but I haven't seen them and landing at municipal in the dark would in my view be pretty dangerous. All of this really doesn't matter though if we don't have things organized on the island first.
We started a similar thread over a year ago and although there was a lot of talk and we even had at least one meeting it never went anywhere.
The Astrum approach is pretty easy to get started and most helicopters can be outfitted pretty quickly to carry a patient.

Captain One Iron