The CEA “Pre-Order” bonuses are included inside the game package. Proof @ 4:23: http://www.youtube.com/watch?v=S1PL2oeqDTY. So I am guessing u didn’t need to pre order to get these. Good news for people who didn’t pre order but on the other hand there is also a code for the Anniversary maps for Reach (In video) and a slipcover!!! 
Reported