From a search, nothing definitive, but the place was evidently quite popular for a course built at the start of the depression...
Danny O’ Neill was a radio personality and a great Irish tenor who lived for a couple of years on Poplar Road. The back of his house backed up to the River Vale Country Club, where he spent most of his time anyway. You can still hear some of his records being played on the radio around St. Patrick's Day. During the mid to late ’30’s many well-known people would come to Handwerg’s River Vale Country Club and play golf there or just hang out for the day. It was the best "open" golf course in Northern New Jersey and people such as Jack Benny, Fred Allen, The Dorsey Brothers, Benny Goodman, Barry Wood, Rocky Graziano, Joe Louis and many, many more personalities, whose names I have forgotten, found that place as a great spot to relax on a weekend. In the days of radio, much of the entertainment came from New York City.