If an individual heir or devisee dies before the hearing, a renunciation may be made on his or her behalf by any of the following, if the judge makes a determination that the renunciation is in the best interest of the parties:
(a) An individual appointed by a probate court to act on behalf of his or her private (i.e., non-Federal-trust) estate, including but not limited to a personal representative, administrator, or executor; or
(b) Someone appointed by the judge with the express approval of all the heirs or devisees of the deceased heir or devisee.