A Specter, Illuminated, is this achi bugged?

[Mamut]

Today I was trying solo achievements from Vault of the Vardens (need only 3 more for glory). I did first two without problems (stacks on fire golem and walls at Cordana without light) but I just cant do the last one A Specter, Illuminated where I need to bring light back to the tunnel between golem and gazer.

The problem is the light disappear when going up on the lift. I watched some videos witch people soloing this achi but noone show how he vent up, the videos start already in the tunnel.

So whats Im doing wrong?

[Deleted]

I was under the impression you needed to at least duo it as you need to have 2 orbs and since it's only possible to carry one per player?

[Mamut]

People on wowhead are saying they also soloed this. There are videos with people killing solo spectres.

[Deleted]

Light disappearing in the elevator is definitely a bug. I soloed it today using the light orb you get from the last boss.

[f4ncybear]

Can't solo on DH tank, don't remember why. Need to be havoc for the specter part.
Only light from Cordana room can go through elevator.