Just started campaign single and co-op on Legendary for 1st time and was able to get all 7 achievements, but no Iron skull or red glowing terminal present in Pillar of Autumn? For me alone or with friend in co-op?
The iron skull should be behind some crates in the Cryo chamber room.
The terminal should be on a view screen saying ‘Incoming Message’ on the LEFT side of the bridge before you see Cpt. Keyes.