I guess the other question regarding the possibility of the wreckage being found is:
is an attempt made to hoist the wreckage (would seem near impossible to me dependent on depth) or simply map and film it? The latter would, of course, preclude
recovery of the CVR and FDR.
A lot can be done with pics relative to structural questions. There's a whole science and experience bank with this. However, if the larger issues are performamce issues of the airplane or crew then the black boxes are a high priority for recovery.
The submersibles have some capability for extraction and lift, is it enough??
Lacking the lift capability (black box emeshed in something too heavy) then some more difficult attempts may be made with flotation devices.
But first things first
lets get the pics and see what the experts recommend after that.