I just did 50 helms for my Kannagi and another 50 helms for LS mates Almace. You can only get 2/3 of the KIs from gold chests. Trust me, we did it this way. One group of 4-6 killing individual NMs while a duo team THF and WHM did Aeolian Edge burn for time and gold chests.
The hardest part about this stage is getting help. Most don't like to come because Briareus drops crap. Sobek is another story. Anyway, just beg some friends and promise them the af3+2 stuff on the next stage.
Also, ppl soloing this slow you down. Takes them forever to solo some of the NMs. btw, on Leviathan, 5am-7am EST is your friend.