Invisibility:
When Playing press Back, Back, Start, Start A, A, B, B, X and Y. This will make so that you will not be seen while playing.

Boot Camp:
After you complete the task of looking at the lights, walk right and go through the door. On the shelf you will find a lock pick. You can use this to pick the lock for the door just next to the entrance for covert ops. You will find a keypad code, which can be used for the left hand door at the start of the level.

If you're lazy, the keypad code is 5656. Use the code on the left door. Through this door are two rooms, Grimsdottir is in the second room. You can talk to her, but of course, hitting her will get you fired.