The cosigner's bankruptcy should not have any impact on the borrower's liability. We don't know what happened or what your father may have done, and we have no way of investigating this for you. If your father won't or can't tell you want is going on, and his bankruptcy lawyer similarly won't or can't explain, consider consulting a lawyer of your own.
I have no idea what you believe your father deceived you about, or why. Perhaps you can better explain what you're thinking.

