I was playing spec ops split screen with my house mate, I played on Veteran and he played on regular. He was on level one and I was on 36. When we were about to start the mission a pop-up message would say his progress would not be saved because he hasnt reach the specific level to unlock this spec op. Anyway we continued and once we completed the mission I was awarded 1 star when I expected three!?! and he was awarded no stars.
Was I awarded one star because he played on regular or because he had not unlocked that specific mission yet? Does the awarding of stars correspond to lowest difficulty setting selected?