Interesting seabed map here from new scientist.
https://d1o50x50snmhul.cloudfront.ne...8264-1_800.jpg
Although related to climate change it shows that the seabed in the search area is predominantly three sorts
A) clay
B) siliceous mud
C) Calcareous ooze
If either of B or C is in a canyon along with wreckage, don't think there is much chance of them finding anything.
Wish them well with the search and hope they do find something to assist with report..