(b) No final account of a personal representative of an estate shall be allowed by any county commission, or clerk thereof, unless such account shows and the county commission, or clerk thereof, finds that all taxes imposed by this article upon the personal representative, which have become payable, have been paid.
(c) The certificate of release, discharge or nonattachment issued to the personal representative by the tax commissioner under section seventeen of this article shall be conclusive in the proceeding as to the liability or the payment of tax, to the extent provided in the certificate.