I just finished a co-op legendary playthrough with a friend, and the end cutscene didn't match either of our armour or helmets. We both had odst helms and i had full odst gear in black but cutscene had white plain armor and an eva variant helm. After the fade to black, it shows a variant of Carter's helm, another helm i don't own. My friend experienced the normal cutscene, and we are both thoroughly confused.
Lone Wolf end cutscene armor mixup glitch?