If the subscribing witness or witnesses are dead, are insane, have moved outside the state, or are otherwise incapacitated to make the affidavit provided for in Code Section 44-2-18, the affidavit of a third person testifying to the execution of the deed and to the genuineness of the handwriting of the subscribing witness or witnesses shall be sufficient to admit the deed to record.
OCGA § 44-2-19