this worked for me. luckily i had a spare drive to throw into my ps3. just threw in a new drive, installed rebug, installed rebug toolbox, turned on debug mode, installed multiman, moved blackops 2 blus to internal and set bd mirror. Created new psn and started game with new multiman. it asks if you want to autopatch the eboot, say yes (you will download the official patch anyways).
Too bad the game blows and everyone camps hard.