I think that you are concerned about having the TurboTax fee paid out of your refund when you suspect that the IRS will place an offset against that same refund.
If the IRS is holding your refund, or they reduced or offset your refund to the point where it’s not enough to cover your TurboTax fees, you'll receive a Request for Payment email, which includes instructions on how you can pay your TurboTax fees (minus the Refund Processing fee, if any).