As to you and the employer while in California, "yes. But, your prospective employer has offices outside of California, and that could create problems for the employer.
Declaratory relief to invalidate a contract provision is not the same as a money judgment for damages. Money judgments are uniformly entitled to full faith and credit under the U.S. Constitution, throughout the USA -- and inversely, they can be uniformly invalidated throughout the USA, under the same full faith and credit theory.
But a decree for injunctive relief is a different matter. Sister-state courts do not necessarily have to recognize the decree of a sister state, if enforcement would impair an important public policy in the sister state.
I'm not trying to be difficult, but this is a very
complicated issue, that goes way outside the lines of mere employment law -- into constitutional matters which can be quite expensive to litigate finally (since the final arbiter of such matters is the U.S. Supreme Court).
Fortunately, it's not up to you to determine your prospective employer's risk.
Hope this helps.
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