Gov. Code, § 22207.6

Notwithstanding any other provision of this part, the board may execute a modification of the agreement, in conformity with the provisions of Section 218 of the Social Security Act and applicable federal regulations adopted pursuant thereto, to include the services of employees of a public agency which has ceased to exist if, with respect to all such services, all taxes required of an employer and an employee under Sections 3101 and 3111 of the Internal Revenue Code of 1954 were reported and paid by the public agency to the Internal Revenue Service in the mistaken belief that such reporting and payment established coverage for such employees and a refund of such taxes has not been requested or made.