I have completed all of the ascendant challenges with my fireteam of 3. We played through all 6 of them every week, getting the bones and eggs in each of them. We also killed the final bosses in each and opened the chests. After 6 weeks of this, doing all of the challenges, I was shocked to find that I had not gotten the triumph "Ascendant Champion" which says "Complete all 6 ascendant challenges". I went through all of the ascendant challenges again, getting the bounty from Petra, and then playing through the whole challenge. I opened each of the chests, walked through the portal, and got claimed the completed bounty. I have done each ascendant challenge twice, some three times. I don't know what I am doing wrong. I have 5 out of 6 completed, so I must have done something right 5 out of 6 times.