If a plan 1 member's prior service as a law enforcement officer or firefighter under a prior pension system is not creditable because, although employed in a position covered by a prior pension act, the member had not yet become a member of the pension system governed by the act, the member's prior service as a law enforcement officer or firefighter shall be creditable under plan 1, if the member pays to the plan the amount set forth under RCW
41.50.165(2) prior to retirement.