Seems odd....even if the tax lien buyer never recorded his deed after foreclosure, I’d think the initial tax lien he bought would show up. I’d also think the tax lien foreclosure judgment would have been automatically recorded in the foreclosure process. Also, did you verify the legal description is the same.....I’ve seen auction buyers who thought they bought one property, but it was actually a different one. But, as long as the buyer gets title insurance, with no exceptions for this, he should be good to go.
If what the tax lien buyer says is true though, he probably realizes now he needs to record his deed and may likely do so before closing.
Where is this property located?