Go down Solusek's Eye as if you were going to Lord Nagafen and you will get the ding at this point.. Note, the elevator button on the lowest floor is on the outside of the doors, near the elevator, but on the middle floor, it is inside the door.
NOTE: If you have slow fall, just jump down the very large and deep hole when you first walk in. It will take you to the lowest level. Do note that you have to steer and land on the last walkway, because if you reach the actual bottom where the wrecked expedition ship lies, you will die.
Find the invisible path over the lava and follow it until you find a shrine over an invisible platform. The path starts at ( 59, -602, -51 ) /waypoint 59, -602, -51. It may be easier to see with Ultravision on (if your race has it). The path lights up when you move and stop showing when you stand still. It is safest to keep moving once you start. The path is all straight. The path can most easily be seen with graphic settings at Balanced or higher.
Pray at the Shrine of Ro at ( -6, -604, -45 ) /waypoint -5.78, -603.88, -45.36 by right-clicking on it.
The Spirit of Ro (65^ Solo) will spawn and begin floating toward you. Wait for it to finish speaking (without hailing it) and then kill it.
*NOTE: If you hail it or kill it before it's done speaking, you will likely have to delete the quest and start over. The shrine does not reappear after relogging or rezoning unless you are on a fresh quest. Update 10/1/2013 - The Spirit of Ro would not respond to a hail and did not speak. Killing it updated the quest. The mob was gray and may be a factor.