I finished the game for the first time and checked all possible endings on
http://pillarsofeternity.gamepedia.com/Pillars_of_Eternity_endings#Where_the_Souls_Were_Sent
To my surprise, you can actually get an offer from Skaen and send the souls to enpower Woedica. However, I can't find anyway to get this option after googling and searching on this forum.
So if you have received this ending, please tell me how to get the offer from Skaen.