I have an idea, now its a shot in the dark and i doubt it would work but..
Try using an alternate account to connect to call of duty, like make a new psn completely, make sure you get the error that says you were console banned, call Treyarc and ask why your console banned, if they say you were hacking say you just bought the ps3 at a gamestop or other game trading store and see what happens.
Just a complete shot in the dark.
Doubt it would work. but if it does please quote me

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