(a) If the duty to replace a public security or interest coupon is imposed on a corporate trustee under a trust agreement or indenture or on a paying agent for the public security, the attorney general is not required to approve and the comptroller is not required to register:
(1) the replacement public security or interest coupon; or
(2) the public security delivered on exchange of the previously issued public security.
(b) A replacement public security or interest coupon is valid and incontestable in the same manner and with the same effect as the previously issued public security.