(a) An order under this subchapter adjudging a community property survivorship agreement valid constitutes sufficient authority to a person who:
(1) owes money, has custody of any property, or acts as registrar or transfer agent of any evidence of interest, indebtedness, property, or right that is subject to the terms of the agreement; or
(2) purchases from or otherwise deals with the surviving spouse for payment or transfer to the surviving spouse.
(b) The surviving spouse may enforce that spouse's right to a payment or transfer from a person described by Subsection (a)(2).