Looking on the bright side, if it’s just missing there’s also the possibility that all those passengers are still alive.
If you look at early articles about this episode, you will note discussions about families that tried dialing phones of the lost passengers.
They would ring and ring or would appear to be picked up then hung up.
Phones out of cell tower range (i.e. underwater) will go directly to voicemail.
It will be an interesting resolution to this story.