Unless the real property is burdened by an assessment, attachment, covenant, lien, levy, tax, or other liability, wouldn’t the property have a value at least slightly more than $0.00?
Or if there really is no buyer:
Does the plan’s governing document permit (or at least not preclude) a distribution of property other than money?
If the document precludes such a distribution, is it feasible to amend the document?
If the plan distributes the real property, the Form 1099-R would report the trustee’s or administrator’s good-faith and prudent estimate of the distributed property’s fair-market value.
A retirement plan should not donate its property, except, arguably, for property that has a negative value, and then only if, among other conditions, the transfer likely would succeed in getting rid of the plan’s liability.