AceSkyKing: Despite everyone having credits to do so, I have not been able to create a Multiplayer game and do an invite for Cabo Del Sol or Whistler. What am I doing wrong?
Nothing, I suppose. Things change in WGTland, by accident or by design.
AceSkyKing: I am wondering what the logic behind this restriction might be? Since these are pay-for-use courses, shouldn't the paying customer be able to choose how their money is spent?
Apart from the logics discussion above, ask WGT! Better chances (perhaps) if you walk into their offices in SF (or a nearby bar), better position to demand an answer if you enter their management or board of owners...
(in short: They keep their business secrets private.)