Some further trolling through the LA Times archive has revealed some further information about the Dana Point project and its elusive golf course. There are a few references to the golf course, but nothing that exactly says that it was completed and in play. The 1946 aerial of the area revealed no sign of a course either.
First up is an advert for the Dana Point development from Mar 9 1928
Next is an extract from an article about coastal developments in CA from December 2 1928, which indicates that $1,000,000 was slated to be spent on the golf course and clubhouse.
Another advert from March 3 1929 - nice sketch of a golf clubhouse, was this the one planned for Dana Point perhaps?
This next article from December 8 1929 says that preparations are under way for houses surrounding the golf course. Was the course there or not?
Moving forward to 1930, this article says that the golf course is either completed or under way. Take your pick.
Finally, this advert for Danaville by the Sea includes golf, so there must have been a golf course nearby.
So there you have it. Was the course ever built? The evidence from these articles and adverts is not conclusive and as the aerial from 1946 shows no signs of a course, I'd have to suggest that it wasn't. Perhaps further evidence will tip this one way or the other.