I think you're referring to US Law, not California Law... everything you said is covered under the magnison-moss warranty act (of U.S. federal code)
Consumer Law: Warranty FAQ
ie anyone in US can make the same claim regardless of state... probably can be used as court argument in other common law countries too
but the reality is that nissan knows not everyone is going to take them to court, and their certainly willing to deny a claim if they think an aftermarket part somehow contributed to the failure of related parts... then it becomes a technical argument
remember that dealers are ALWAYS incented to do warranty work that is not obviously out of warranty... they will have approval levels up to ~$5K, and anything under that they can do at their discretion... they are reimbursed from the factory for the work they do, so the dealer is the least likely to turn you away... if they do, find another nissan dealer - dime a dozen