1) First reports are almost always wrong;
2) PPRUNE rules specifically forbid wild speculation re: accidents.
It's always sad to hear about accidents, but gratifying to know that in this case they all got out safely. Given that, some things about this event are interesting right off the bat. Overwater approach at night, eh? Hmm.
A dual engine-failure is such a remote possibility that we don't even consider it a threat anymore since the invention of containment rings for Rolls Royce/Allison engines. That leaves fuel as one of very few common factors between the engines, so let's assume that they had sufficient of that stuff onboard and let's hope it was good, clean usable stuff.
The translated report did say that the crew had trouble getting out of the ship. Why would that be? Was it upside down in the water? The mention of it sinking so quickly is curious too. It might lead one to believe that the floats were not...you know, inflated. Combine that with no radio distress call and it might make one think that the impact with the water was, err...how to put this gently...unexpected.
But that's just speculation, and we don't want to get into that until we learn more. For now, let's just be happy that they all lived.
according to the first reconstructions, have lost power and consequently from la altitude of 300 meters.
Yup, I'd be saying that too, right up until they could prove otherwise. But from 900'?? Hey, how's about one of you guys squeezing the trigger and yelling "MERDE!"