Roommate Side Swiped My Girlfriend’s Car In My Driveway And Has No Car Insurance. Seems Unwilling To Pay Her Deductible To Get It Fixed.

So as the title states my “roommate” if I can even call him that, recently side swiped my gfs car going down the driveway last week. He informed us when it happened but also informed us at the time that he has no insurance. His registration is also expired on the car by 5 years if that’s relevant at all. My gf has uninsured motorist as part of her policy and we’re just asking that at minimum he pays the deductible. He seems unwilling to do so and just keeps saying he has no money right now and doesn’t know when he will. He’s a very flakey individual so this really just tells me he’s hoping this just goes away. I guess what I’m asking is what would be ours or hers next steps in guaranteeing reimbursement for the cost of her deductible. If at all any recourse. Just looking for insight from others that may have gone through a similar situation and what the outcome was or could be. This happened in California.