SamSpayed: It might be a limited manpower and priorities issue. Maybe they were only permitted access to the Lanai course for a few days.
Well possible. Add that the full course may not be suitable to WGT in yardage, as they have to use the existing tees. IMHO, this applies to Bandon Dunes - all their courses are too short for our top tiers.
SamSpayed: Maybe they already have all the photos and information they need to develop it into a full 9 or 18 hole course, but they just don't have the manpower or the time to do it.
Unlikely, IMHO. Usually, the full course is published in direct sequence to the CTTH, and they are all US Open courses, except Wolf Creek. There must have been a good deal for WGT involved, and I assume they revisited it for the full course.
conjectures, more conjectures...