In this paragraph I was including the possibility of somebody blowing deliberately the station with dynamite for example.
Those things are expensive so the question to ask here is if the station is still lying in the seafloor or was removed by somebody. If is possible to recover it, even partially, could make a big difference for the research team.
I remember putting into the ocean a cylinder full of sensors. It was relatively small, an R2-D2 sized thing or so. The main researcher of the oceanographic campaign was literally sweating with the idea of some chain breaking in the process and losing the small cube property of the university. Each time it was used was like dumping the economic equivalent to a luxury car in the open sea hanging on a chain and hoping that all went ok, several times in a day.
The depth is an issue because a submarine can't go deep enough to be undetected there. It'd be visible to aircraft and boats in water that shallow.