Level 51 - The Tablet

I picked up a quest called "The Tablet" from an NPC named Count Misfortune. I am supposed to locate a tablet on the ocean floor in the sunken remains of the city of Misfortune. I've searched the forums and cannot find a specific location where this tablet can be found. I've swam for hours and about ready to give up for now. Does anyone have any idea where the table location is?

Thanks in advance.