Their death would be in a fraction of a second.
At the briefing, someone said the last word from the craft was that there was a minor problem, that was followed and that the problem was worse but manageable. Then crackling, then static ever since.
Even if they were "only" 2,000 feet down, an implosion would be instantaneous. Sometimes on those crafts, a leak will start at a certain depth, and going deeper seals the leak. UNLESS it is a microscopic failure of the pressurized hull. At that depth, each person was crushed into a sort of jelly with bones.