Respawn time of this is somewhere in the ballpark of 2 hours. It is not affected by a bard at this point zoning in/out and will simply respawn if you sit in the zone. For the Metala portion of the fight hide your casters behind the wall as there is an AE silence.
We got fairly close to her before she showed up on track. She's at the northwest bend of the square area on the western part of the map (to the SW of Avatar of Agony and NW of Avatar of Suffering).
From zone-in and up onto the skyway, hug right until you get to the third building at the west end of the zone where you'll find a bruised woman at (+220, +845, 0). Keeper of Present Lore is also there.