Fight your way out.
- Having survived the onslaught of the Hive while Ghost worked to open the doorway, head through it.
- Go on through to the room with the pool below the walkways.
- Go to the left, and up to the walkway above, fighting through the Acolytes that are in your way.
- When you reach the jump up to the walkway above, expect to encounter a group of Thrall.
- Make it through the large control room.
- Go on through the back left door on the raised level.
- This will end the mission.