Oppenheimer will stay at Apple. His official Apple bio page is still up, though they have not added his new role. From his Goldman Sachs bio page:

Through his positions as CFO and Controller at Apple and Divisional CFO at ADP, Mr. Oppenheimer has significant experience in the preparation and review of financial statements as well as capital and risk management. He also brings to our Board experience in the oversight of technology and technology risks, which he has developed in connection with, among other things, his oversight of information systems at Apple. Through his service on the boards of directors of not-for profit entities and as CFO at Apple, Mr. Oppenheimer has developed experience in corporate governance and leadership.

Note that both the Apple bio page and the Goldman Sachs page list Oppenheimer’s Apple position as (2004-present).