Why not? If Echo has been able to do scan of a particular area and it is showing clear signs of the wreckage, ...
Why not? Because there is no way to associate 100% a particular scan with a wreckage, at the best you get a something that may look like a wreckage. You still have to get down there to verify. Plus to get a reliable scan they have to lower the submersible and we know they haven't been doing it.