Three years ago John and Marcia Friede had promised to give San Francisco’s deYoung Museum “their entire 4,000-piece collection of tribal art from New Guinea, generally regarded as the best of its kind in private hands. The museum built an 8,000-square-foot wing to display the Friede collection and helped publish a lavish two-volume catalog of the works. Today the gift is in doubt, and many wonder whether the collection will remain intact.”