As Gabrielle said, there's a way you can destroy their legend, kill their mommy and destroy their future and still walk around, all the while knowing everyone knows you're public enemy #1, but are untouchable. It's all in the dialogue. ;)

What are those dialogs options? Do you have to tell that the Republic sent you?

[SPOILERS]
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From memory, you need to:

a) admit you released the gas

b) claim it was a malfunction

c) say that they can't kick you off, you know too much about the kolto situation

d) threaten to reveal the secret about the kolto being destroyed if they kick you off.

At the end of these the fish people will have no choice but to call it evens with you. :D