The UW report appears to contradict rolling. Rolling is a stability issue with large waves abeam and with a heavy water-laden load, they would not have capsized directly, whereas the wind and waves, apparently astern at the time, forced them down bow first. Once under, all stability in any degree of freedom is a moot point, however in an upside down and bow downward position, I doubt they would have had any inherent tendency to roll back upright on account of the hulls bouncy, no matter how they eventually hit the bottom, because the hull would have been flooded immediately by the water flowing in to replace the lost cargo. Upside down with a small amount of air providing little buoyancy and the weight of the rest of the ship below that center of action would not tend to upright the ship. It would probably just continue a nose dive to a more vertical attitude from which almost any final bottom position might result.