Zana Untainited Paradise Bug, Mission Failed

I finished my Untainted Paradise tonight, first i've gotten pretty excited, anyways after i killed the bosses the quest updater showed a wierd message, then when i turned in the mission it sayed mission failed as the other masters mission was not completeted.

http://steamcommunity.com/profiles/76561198154945522/screenshots/

This is the screenshot of the bugged info, I forgot to take a picture of the bugged mission failed, I apologize.