It's a sentence from dragonball, the hearer (悟飯) just asked the speaker to create something to wear that could hide his identity without looking like a kind of body protection.
どってことないじゃない!悟飯くんだってばれなきゃいいんでしょ?
That's no big deal! It's gonna be ok as long as you don't get busted right?
I don't get the meaning of だって here, I know that most of the time it can be replaced by either も or でも but I don't see how either one would fit here.