The chest is up there.
It is located above the fel core making it almost impossible to get to unless you're a demon hunter Had to use glide, fel rush and infernal strike to get to a vantage point Loot: x38 Edit: this can now be easily travelled to using the warframe leap ability from the vindicaar special ability.
You are essentially blind most of the jump.
My coordinates are on my mini map and at the top of the screen.
I had previously completed the quest line sending you back to the Vindicaar, then returned via the new beacon it opens.
You will need to circle the building and go behind it, climb up some rocks, and do a few jumps to reach a narrow ledge.
I, personally, feel like that was the big finish.
It is much easier to get to now then it was, when it was located on the floating tower in the north off the map.