BAA and BDCA and ATLB are gov entities.
BZE does have published instrument approaches, 6 to be exact. An ILS has nothing to do with this but, the ILS will be commissioned this spring.
Since Belize is an ICAO member, Belize can not make up our own rules, they must follow ICAO recommended standards
Public fueling of acft in Belize is only allowed at MZBZ and TZA.
The local operators have eveything to do with aircraft operations within Belize. Who do you think funds civil aviation in Belize.
There are many other reasons that SPR will not become an international arpt, these are just a few, I doubt if you have the education or knowledge to fully understand them.
Acft arriving to Walkers Caye may only continue to Nassau or back to their original pt. of origin And, the Bahamas CAA would not license another international airport under similar conditions today.
Anyway, if it ever does happen, I'm sure you'll be the first to know.