Changi jail is in Singapore, HMS Hood was sunk in the Denmark Strait (between Greenland and Iceland) so he couldn't have jumped overboard before she was sunk. Are you sure your not getting mixed up with HMS Prince of Wales. She was present when the Hood went down and was subsequently sunk in the Far East.
Many men served in Hood- some of them were transferred as late as the very evening she sailed to meet Bismarck. It is possible that some of these men considered themselves "survivors", but this is technically not true. As we see it, for one to be a true "survivor" a man first must have been onboard the ship when it sank and secondmust have been rescued alive after the sinking.In the case of H.M.S. Hood, of the 1,418 men aboard that day, ONLY THREE were pulled from the water alive: Midshipman William Dundas, Able Seaman Bob Tilburn andOrdinary Signalman Ted Briggs. There were absolutely no other survivors ever picked up. Anyone (other than those three) who claimed or claims to have been rescued from the water is either confused or not telling the truth.
I managed to get the service records for my paternal grandfather and great-grandfather. It's quite straightforward and the Royal Navy Service Certificate lists all the ships served upon with specific dates. All you do is apply here(link): service records sar form requests
Everyone salty knows this already, but a late transferee from the HOOD was none other than future Dr Who and Worzel Gummidge, Jon Pertwee. Good luck Cindy, you might try the Naval Historical Branch if you luck out.World War Two Naval Losses