I have 30 years of real life experience in California. They don't need to prove anything. When bushings, shocks, struts etc go out and you have aftermarket springs, they can and will void it. By they, I mean EVERY brand. With ICE cars, ECU tunes are big. They can void the ENTIRE warranty, again without PROOF but with simple implication. For you to fight it, you would need to SUE. Therefore, the burden of proof is on the consumer. People that say otherwise, are enjoying to hear themselves talk. The factory can make unilateral decisions and move forward. It doesn't mean that they can't be held accountable (again by suing). But it means they don't need to PROVE anything. There is no judge and jury to determine the path forward. That person is a FACTORY REPRESENTATIVE. Good luck to anyone trying to Sue tesla or another car manufacturer. Can you recall any lawsuits where the consumer won for wrongful void of warranty? I didn't think so. That precedent will not get set because they will FIGHT.