Zombie Stomp 8

I was playing halo ce on the chief collection and played pillar of autumn on legendary with the bandanna skull on and got the achievement for completing the level. However, I continued to play legendary with the bandanna skull on and did not get credit for completing the other levels and I was wanting to know why. I have heard the bandanna skull disables achievements but this can't be the case considering I got the achievement for completing the pillar of autumn with it on. Can someone from 343 please explain to me what is going on? Thanks, Zombie