My girlfriend and I have been playing the Master Chief Collection on Legendary; Halo CE, 2, 3, and 4.We've beaten them all and all of the levels of all 4 games indicate legendary completion. We have not received the achievements for the legendary completion on Halo CE and Halo 2.
Halo Waypoint shows that we have only completed 5/10 levels on legendary, despite the game showing 10/10 for Halo CE. For Halo 2, Halo Waypoint shows that we have completed 11/13, again, despite the game showing 13/13. Because we have not "unlocked" the achievements for Halo CE and Halo 2, thus, not giving us the "full legendary" achivement for the Master Chief Collection, we have been unable to get the Helioskrill armor for Halo 5.
I talked to support and they tried to provide some options, ie. deleting and re-adding profiles, turning the xbox on/off,etc, and nothing has changed this. I'm sure we are not alone with this issue, and I'd like to think someone could provide assistance considering this is not an easy task taking up a lot of time.
Hope to hear from someone soon.