A. They weren't wearing pfds. The captain had to run back in the cabin to get them after the accident. I'm surprised that they even had an inflatable that nobody was wearing.
B. This reads like an adventure story, with no mention of lessons learned.
It's easy to forget that we don't wear life jackets because we can't swim. Wear them instead to help keep your head up while you get your breathing under control when you first go in, and to keep you above the water after your arms and legs stop working in the cold water - which happens well before hypothermia does you in.