It will be interesting to see what, if anything, is recovered from that box, especially considering that the box is probably being recovered from a depth that is near the absolute design max of the box itself.
If the box is of modern construction, it might use mil-spec multi-error-detection and correction flash memory and not a metal or plastic tape, so it might be in pretty good shape. I think I read that if there is no mechanical damage or long exposure to fire, they are amazingly sturdy.