I might say, this quest took me a looooooong time. I figured any charm would be better than none but after the hours and hours, I was quite frustrated.
We did the tunnels first, which wasn't bad but took forever, although eventually we got the two drops there for 3 different characters. The first few visits to the windscorn landed one insignia there so I moved on to finish the quest for the character with the 3 insignias.....well, it took forever. I prolly killed 100+ Guardians without seeing anything. Finally, after another unsuccessful night, I logged and my bro went after them and Boom, two insignias in 10 minutes.
I was just glad to have the quest done. I was really starting to go crazy on all the time I spent in Dulak. Although the loot was decent, a lot of gems.
Do this quest if you have nothing better to do. I mean that. Or if you are low enough to get decent exp on the mobs. Otherwise spend time leveling or doing AAs and you’ll end up farther along in the long run.