I'm not very familiar with the US legal system, but doesn't Federal Law override any state law if there is conflict? Presumably any antitrust action taken by DOJ would be in accordance with federal law, so the state laws shouldn't matter?
In particular for the noncompete ban, I believe that trying to enforce a noncompete-adjacent action like this would open you up to being sued by the employees who would have been hired, and the hiring company, in California court.