A financial institution, on request, may pay sums on deposit in a multiple-party account to: (1) One or more of the parties, whether or not another party has a disability, is incapacitated, or deceased when payment is requested and whether or not the party making the request survives another party; or (2) The personal representative, if any, or, if there is none, the heirs or devisees of a deceased party, if proof of death is presented to the financial institution showing that the deceased party was the survivor of all other persons named on the account, either as a party or beneficiary, unless the account is without right of survivorship under section 19-602.12.