Notwithstanding any other provision of this article, if so agreed to in a memorandum of understanding reached pursuant to Chapter 12 (commencing with Section 3560) of Division 4 of Title 1, as it pertains to represented employees of the California State University, the employer may pay, in addition to the employer contributions, all or a portion of the employee contributions required for the benefit payable pursuant to Section 21574.7 or the employees may pay, in addition to the employee contributions, all or a portion of the employer contributions required for the benefit payable pursuant to Section 21574.7.