I will suggest that the problem is interturf bureaucratic dithering.
The coast Guard had the lead and the Coast Guard is Department of Homeland Securtiry. The implosion is said to be heard by the Military or the Department of Defense.
The event happened in international waters.
Perhaps the State Department thus became involved.
Dithering bureaucrats just could not act instantaneously
All rescue could have been right on top of the spot. Result would’ve been the same. There is no rescue at that depth