It may not be done as a stand alone game, but it could be done as DLC or as a game in Playstation Home. The Okinawa Golf Resort could easily form the basis for a mini-golf course. Send the ball through the Okinawan houses, avoid trap doors, negotiate opening and closing shoji doors, etc.
The Euro Classic course could also be made into a mini-golf course. This course would take players inside the castles.
There could even be some new concepts, such as a Pirate themed course. Or courses based on other Sony games, such as a Ratchet and Clank themed course.