Majestic Achievements Glitched

I have them but my friends cannot unlock the achievements Birds of Prey and Pigs can fly. We have tried endlessly to get these. Yes we are on the right maps and yes we are jetpacking for Pigs can fly. We are also getting the airassination medals but not the achievement. Thanks and any help would be appreciated.

A lot of people having the same problem, there’s an another thread with the list of glitchy achievements:
https://forums.halowaypoint.com/yaf_postst226518_Halo-4-DLC-s---achievements-not-popping-up.aspx
Please fix it 343!