This quest step says this, "Have an ally invader defeat four opposing Guardians in a single invasion three times, OR defeat four opposing Guardians as an invader. As an invader, defeat 25 opposing Guardians in Gambit." I have invaded in gambit more times than i can count, and everytime i kill 4 opposing guardians nothing happens. I even get the "One Man Army" medal thing. Ive done it three times, and still the quest hasnt progressed. it hasnt moved. It hasnt changed. What is happeneing? I even looked up a tutorial to make sure i was doing the quest right, but it just wont complete. Anyone?