You just fell into the trap I've fallen into. Asking why they would design an event at best excluding 1/2 the population. At worse making an event for raiders that decreases the event for many more people.
Still lots of people struggling to do heroic content. Still many more guilds unable to kill Avatars.
So I guess I need to go back to why ask why? Since they have the event laid out and are unwilling to change it to include more people.
I checked the rest of the zone, and only those mobs have the update feather. They do drop the updates, but they're heroic and the mission (and previous missions in the 30s) is solo, so I /bugged it.