I'll stick my neck out and hazard that the French have had a good long look through their satellite radar and seen something interesting. If the US (and maybe Russia and China?) can do the same with their views within a few hours of impact, then the mystery might be coming to an end.
And there's still time to catch the sonar beacons in time to have some power left.
Then again, Titanic was found in the end, with only approximate chronometer/sextant positions, so it's not forever hopeless if a ~ten mile position is known.