Legal Question in Family Law in California

She is entitled to her community share regardless if she remarries or not. It should have been allocated in the divorce.

Remarriage only affects spousal support (and in a very limited way child support). Whatever your divorce settlment agreement/judgment says still governs the retirement. If it was not addressed in the judgment, you will need to reopen the case on the grounds of omitted assets and have a determination made on her entitlement.