If it has settled IN the bottom, there is no water pressure.
As an earlier posted noted there would be a hydraulic pressure from, say, mud, but the problem is that that increases the suction problem.
You can all disagree as much as you want in theory, but numerous vessels have been torn in half by that hydraulic suction caused by lifting them from much more shallow depths.
In fact, positioning ships and rigging cables is pretty standard procedure down to about 50 meters. - After that it becomes very, very difficult, and the focus turns to removal of the crew rather than salvage of the vessel.
As far as asymmetry is concerned in actual hull collapse, 625 is nowhere near crush depth for any DSRV that I am aware of.
Using your "theory" think of the following:
A scuba diver in one hundred feet of water puts his foot on the muddy bottom. Immediately his foot would be subjected to 44psi downward force. Depending on the size of his foot and the type of foot gear he would have one thousand pounds or more pushing down on his foot. Amazing that any divers ever surface after getting to the bottom.