There's your semi-proof of its existence. I also learned that it can show up in the first past phase on the map. I still can't target it, but I rolled over it on the mini-map. I also noticed that it wasn't on the map when we first got into the past, but instead spawned at the same time that the adds spawned when trying to attack the crystal. I was unsuccessful in attempting to target it again. But based on the location, the presence does seem to move a bit, as I have seen it directly over the throne before. I also find it quite interesting how similar the past looks like Makeb, specifically the Toborro's Courtyard room.