Young, the PGA Tour rookie of the year, received a release to compete in the Asian Tour event. It was his sixth runner-up finish in the last 16 months.
He caught Ancer briefly on the front nine until a two-shot swing on eighth home — Ancer made birdie, Young made a bogey — that restored Ancer's two-shot lead.
Lucas Herbert of Australia had a 65 and finished third.
Young now heads to back-to-back elevated events on the PGA Tour in Phoenix and Los Angeles. Ancer, who joined LIV last summer, has two weeks off before LIV Golf begins its second season.