I got this info from a commercial diver friend of mine.
The watches were made from extra titanium that was left over from making the sphere for the diving sub. Omega strapped two to the outside of the sub, and one went on the lander that had gotten stuck in the mud. As can be expected, they're very thick, large dive watches which were tested previous to the dives at 1,500 atmospheres.
The watch is called the Ultra Deep (in blue lettering on the dial) and looks to be based on the planet ocean, but also seems to have a vintage Omega Grande look to it. On the case back is the depth 49,*** ft. In actuality though, 1500 ATM is 50K (the Rolex Deep Sea Challenge was also tested to 1500 ATM).