Also, since the crew survived, why are they so concerned to get the voice recorder? Is it just because of the recorded alarm information, and if so why keep referring to it as a voice recorder and not a black box.
Just like with aircraft accidents, the conversations can provide as much (or sometimes more) value as the data. It gives you insight into decision making, details that may not be recorded in the data ("I was just in area XYZ and I saw sparks coming out of one of the vehicles"), etc.
Russian criminals were stealing rich boys million dollar yachts a few years ago.
They would board the ships when the skeleton crew was off the ship.
They would take the transponder, and put in model hobby ships.
The owner, and authorities thought their yacht was exactly where they left it.
The Russian thieves would take the yachts back to Russia.
(I thought is was clever. They stole millions of dollars in terms of yachts, and were eventually caught buy Interpol.