Situation with No Contact Solar Installer in California

My installer finished my solar setup in early December, unbeknownst to me he was planning on shutting down his company and moved to another state. He never accepted his final payment but has gone no contact with me and his other customers. I'm assuming because he doesn't want to be held accountable for his worksmanship guarantee of 10 years. What should I do in terms of attempting to pay this guy? I'm assuming there is no recourse if there's a problem with the installation under warranty with a company that no longer exists.