Really sorry you're going through this. Start by filing a complaint with the CA Contractors Board if they confirm the contractor is unlicensed. Follow up with your insurer in writing (keep everything in writing... that's really the best way to get their attention) and ask to escalate the claim internally. It’s also worth speaking with a construction defect or insurance attorney. Many offer free consults. Keep everything documented and check if your policy includes coverage for temporary housing (ALE).