Is it permissible to use a portion of the usurious interest paid by the bank to cover the "account secrecy" fees that were imposed without prior knowledge or consent?

You are not permitted to take any of the interest as compensation for the confidential information taken from you. All of the interest must be disposed of for the benefit of Muslims and given to the poor and needy. The holder of this interest is not allowed to take from it for himself or to use it to protect his own wealth, even if what was taken from him was unjust. If one needs to open an account with a usurious bank, he should limit himself to what fulfills that need, such as a current account, without a savings account.