Quite a few survivors were listed as dead in the time soon after the wreck. Off hand, I recall the Stengels, Mrs Malvina Cornell, Leontine Aubart and Mauritz Björnström-Steffansson.
An example of the reverse was Alfred Cunningham, one of the H & W workers, who was incorrectly listed as a survivor. He was probably confused with Andrew Cunningham, a steward, who survived. He is still named as a survivor in Shipbuilders to the World, a semi-official history of H & W.
Even people who were not on board were listed as dead, notably George Eastman, the Kodak man. Conversely, I've seen Lady Cynthia Asquith listed as a survivor, but she was not on board either.