I can't believe every time I come here this thread is at the top of the forum with almost 20 Mil views.
Now listen. They are not going to find it and if they did any evidence would be useless after getting dragged up from 3 miles deep.
Jeez let it go and move on. Sometimes s*^t happens and you can't plan for events like these.
And if you think cell phones would have any useful info after being submerged in a saline solution at great depth for such a period you may have to go back to school for some more chemistry and physics classes.