We took down the turtle with a PUG, and I got the shoulders coin. 6/6, and I never need to enter the 16th Hall on that character again.
Then I tried to do 2.8.3. That is a three-person instance, and one of our members was a Lore-master who could not mez (traited it away), remove corruptions (necessary for the fight if you don’t keep them mezzed), deal damage (that we could notice), heal (he didn’t), or tank (he’s in a robe). But he could repeatedly apologize over voice chat for breaking others’ CC by misunderstanding “right” and “left.” In a 6-person group, you have room for one sub-par member. You do not 2-man a 3-person instance.