I think you are conflating several different types of liability here.
If: i)your accountant messes up due to negligence or worse, ii) you get audited, and iii) it turns out you owe far more than you thought, then you are liable to the Govt for the extra amount owed. The accountant may be liable to you for professional negligence, damages etc. Your damages against the accountant are not the extra amount owed (because it is what you should have paid in the first place), but losses caused by the mistake. In the above scenario, the Gov't may assess a "penalty" and/or "fee" for late payment of taxes, but those fees are usually waived and/or extremely nominal. In the above-scenario, criminal liability simply does not happen. The above is not legal advice.
