Click on the Treasure Chest underwater. ( -66, -8, 510 ) Copy/waypoint -66, -8, 510
Click on the Water Logged Scroll on the beach. ( -92, -3, 464 ) Copy/waypoint -92, -3, 464
Place 5 fish on the basket of fish at ( 20, -3, 451 ) Copy/waypoint 20, -3, 451. They are movable, and will be along the shore or around the edges of pools of water, but not actually in the water.
After moving all five fishes to the basket, you will receive a messages "A deep sounding tone echoes along the coast as the smell of rotten flesh drifts in the air" and Fhoorl-Kurrat with rise from the depths. Kill him to get the key.
Return to and open the treasure chest to receive the Hand of Glory. ( -66, -8, 510 ) Copy/waypoint -66, -8, 510