RotorheadS92: You have to appreciate that the questions that you ask are not really relevant. If you can operate IMC low over the sea (as you can when doing SAR in a helicopter) then there is effectively no appropriate VMC minima. At night over the sea you can't really be VMC in the same way you are overland with lit towns etc. It can just be inky blackness all around you.
However as others have said VMC helicopters is COCISS, and as the back seaters could see the rocks on the camera that means that they were VMC, but given that you can be VMC and still not see anything it's not really relevant.