Always a tough spawn for me, Lv.90 NEC with a j5 healer
Had a 85 ROG help me with a j5 tank and we were able to get the Shaman down. Dropped the Shield of Rituals for me (a bit of a downgrade but it looks much cooler than my last shield I picked up in The Grounds).
But
I'll usually die if I try to solo, just because of the adds. What I will typically do is cast my mesmerize on 1 of the 2 adds, pull Shaman and the add out a ways, and mesmerize the second. If, by sheer dumb luck, 1 or both of the adds don't aggro back when the mez breaks, I can take the Shaman Ixchell out without much hassle. Usually I'll have 1 of his adds and things get hairy quick