This works quickly for me every single time I do it:
1) Kill Grimling Chieftan, kill Grimling Defenders, then ***wait for owlbears to show up***
2) Kill ONE of the owlbears standing just outside the hut, then run to the owlbear caves in the west and kill ONE of the owlbears just outside the cave.
3) Run to wolf caves and wait for defenders to spawn, kill them.
4) Run to camp where named spawns and kill her, hopefully you get eye.
I know this is similar to other posts here, the difference being step 2. From my experience it is NOT a random event, nor does killing Growlik or packleader have anything to do with it.
**I don't know why killing the 2 owlbears causes them to attack every time but it does. Everytime I did this the owlbears attack on the first shot**
Hope this helps everyone and Good Luck!