(a) The judge will require testimony if someone contests the approval of a self-proved will, codicil, or revocation, or submits a non-self-proved will for approval. In any of these cases, the attesting witnesses who are in the reasonable vicinity of the place of hearing must appear and be examined, unless they are unable to appear and testify because of physical or mental infirmity.
(b) If an attesting witness is not in the reasonable vicinity of the place of hearing or is unable to appear and testify because of physical or mental infirmity, the judge may:
(1) Order the deposition of the attesting witness at a location reasonably near the residence of the witness;
(2) Admit the testimony of other witnesses to prove the testamentary capacity of the testator and the execution of the will; and
(3) As evidence of the execution, admit proof of the handwriting of the testator and of the attesting witnesses, or of any of them.