Appeal rejected, heading to tax court. 5 figure case.

I distributed a rental property from my SDIRA in 2020 as a cares act withdrawal. There was a mortgage on the property. The irs wants taxes, penalties, and interest for the banks portion of the property (the non-recourse loan). My taxes were flagged because the IRA put the gross appraised property value into the 1099R taxable amount box (ie not considering the lien). They also checked box 2b which says "Taxable amount not determined", but the IRS has ignored that check and focused on the taxable amount for the deficiency.

Does anyone have any guidelines, a court case, lawyer recommendations, etc. that could help me defend myself in court? The IRS wants something in writing: the appeals officer asked under what authority should the lien be considered in the distribution, then denied the appeal when my CPA suggested we compare it with the distribution amount if the property was sold and the note was called due.

Other similar like-kind distribution examples would be helpful to. If a like-kind property is distributed from an estate when someone passes, the estate tax value doesn't ignore the lien. Is there other like-kind distributions where the lien is considered that I could liken this to? It would be really helpful if there is tax code or written rules I could provide the IRS.

Any help or recommendations are appreciated, thanks!