(a) Subject to Subsection (b), amounts in a joint account may be paid, on request, to any party without regard to whether any other party is incapacitated or deceased at the time the payment is demanded.
(b) Payment may not be made to the personal representative or heir of a deceased party unless:
(1) proofs of death are presented to the financial institution showing that the deceased party was the last surviving party; or
(2) there is no right of survivorship under Sections 113.151, 113.152, 113.153, and 113.155.