Hammond Robotics feels your pain. The makers of Titan Fall 2 would never do something like this to their community. They actually care. (I grinded so long for these.... And they broke...)

It hasn't worked since well before Rise of Iron. If I recall correctly, it was a hotfix around June 2016 that broke them. Bungie will never fix this or the disappearing skeleton keys and SIVA key fragments.

I farmed for 5 to 7 hours to finish my quest for my new monarchy cloak and I was so hyped to see the respawn animation, but nothing happened, I looked up what was wrong. As it turns out, we can't have an Iron Lord artifact equipped or the special animation won't work. Bungie absolutely needs to fix this by the time Age of Triumph is released.