I wish I knew about this beore completing it…
Note that all but two of the NPCs give credit when you *heal* them. Two of the others are trapped/rooted and need the root clearing ability used on them instead in order to get credit for them. If the NPC does not disappear, try the other ability.
You can prob also buy other covenant mount when 9.1.5 release, with free covenant swap
Honestly thought the assault was bugged since this quest never seemed to appear in the rotation. Like, 11 weeks is kind of a long time for a quest to rotate in.
Another tip, don't 'help' the full amount of NPCs prior to finding all of the achievement NPCs. Doing so makes the achievement NPCs not appear.
It’s a shame it’s not an account wide meta, otherwise if you missed it you could just do it on another toon.