Implosions require a lot of pressure, so whatever took them out did it while they were still deep.
My guess is it happened as they approached extreme depths. Metal fatigue and poor design aren’t always instantly apparent, but they stack up exponentially. The same way the CEO had piloted it down before he did again, then BANG and done. Would have been practically instant and without warning.
If kids shouldn’t suffer for the sins of their grandparents then why should other kids suffer for the sins committed against their grandparents?
You can’t starve one man while feeding another for years, then give them both equal food for a few months and assume they’ll be even. You by necessity have to give the starving man more, and regardless of the fed man’s complaints it isn’t unfair for him to get less - he’s literally been getting more the whole time and is perfectly healthy.