Re. recovery of bodies I have to tell you the main problem would be getting each one to the surface in one piece. I have some experience in this.
Google 'saponification' to understand why marine creatures are not required for total, rapid decomposition in sea water. Sophisticated analysis of crash injuries is simply not possible other than bone fracture. If I were a coroner (notoriously hardened individuals) I'd personally excuse myself from said process.
Sorry for the reality check but facts are facts, I have seen what happens and it will haunt me until the day I kick the bucket myself.
I would strongly urge the recovery team and relatives decide to leave the remains where they are and conduct a wonderful, spiritually uplifting service on the site.
There will be no trace in another year or so. Summary: I think that's more fitting to leave them be. It's how I would prefer to disappear from life under such circumstances, if I had to. Personally speaking.