(a) A message is as valid, enforceable, and effective as if it had been written on paper, if it:
(1) bears in its entirety a digital signature; and
(2) that digital signature is verified by the public key listed in a certificate that:
(i) was issued by a licensed certification authority; and
(ii) was valid at the time the digital signature was created.
(b) Nothing in this chapter shall be construed to eliminate, modify, or condition any other requirements for a contract to be valid, enforceable, and effective. No digital message shall be deemed to be an instrument under the provisions of section 336.3-104 unless all parties to the transaction agree.