My post #27 above clearly states that Tillinghast's 18 hole course opened in 1918:
The Metropolitan Golf Links was beset by financial problems,however. Baird and Hipwell underestimated the costs and consequently,on December 19,1915,a small successor group of former Quaker Ridge country Club members formed, and chaired by Otto Elsass. At a meeting held in the Hotel Majestic on January 5,1916,the Quaker Ridge Golf Club was founded with 28 original members. Most notable of these was William Rice Hochster,who was added to the organizational committee at this time. The new group purchased the Quaker Ridge Country Club's lease on Febrauary 18, 1916, and legally incorporated on February 21, by this time boasting 92 members. Encouraged by positive recommendations from the leading architect A.W. Tillinghast and Baltusrol professional George Low, they quickly purchased the land they were leasing from Bradford Rhodes for the sum of $175,000.00. Tillinghast then proceeded build 11 new golf holes,while at the same time radically revising seven of the old holes. The new 18 hole course opened for play on June1, 1918, and is now generally regarded as a Tillinghast "original." For several years the course played to a par of 70 at 6173 yards.
When the time came in 1924 for a major revision of the course, Hochster was there to carry out Tillinghast's plans. He lived in a house just to the right of the first green. That change came after the club purchased 28 acres from Martha LaFurgy for $35,000.00. The changes that Tillinghast recommended and Hochster implemented in 1924 brought the course into basically its present configuration. Four new holes(3,4,1213) were built at that time,and two others altered-the first green was moved from behind the fairway bunker, and the second,originally the third, was given its dogleg. At the same time, four holes were abandoned. The old second hole was a short par3 near the tennis facility that played to a punchbowl green. The fourth at that thime played from behind the 14th tee over the 13th green,to the present fourth green,directly over the "pit" to the left of that green today, but which in those days extended completely across the "front" of the green. The old 12th hole was was a par3 to the right of the present 11th green,playing over a creek. And the 13th then was a short par4 that made a sharp turn to the right near its green,which was situated out in front of today's 14th tee.
The above is from an article in Met Golfer that was sent to me by the MGA historian a few years ago. I'm trying to contact him again to find out who wrote the article.