When not at fault, my insurance or his?

I’m sure this question or some variation has been asked before, but any help would be greatly appreciated.

I was in an accident over this past weekend that I was not at fault for (he blew a stop sign right in front of me and I hit the bed of his truck going 50mp). We both stayed so CHP could do a full report and he was ticketed and accepted fault on the scene. However, my car is totaled. My car’s cash value is between 12-15k.

I’m in CA, where limits are low and he was an older guy in a beater 90’s pickup so I wouldn’t be surprised if he is only carrying state minimums (5k). I have full coverage and much higher premiums because the car is financed (5k left). Police report should be ready in a few more days, but I’m trying to decide which insurance to file under. I started a claim with mine and I paused it once I got his insurance info from the CHP office. My deductible is high (2k) which I’m now realizing is dumb but I can afford it at this time, it’ll just tighten up my budget.

If I file under my insurance, is there anyway to get my deductible back? I want to get the ball rolling sooner than later because my car is sitting in a salvage yard right now wracking up those fees. Is filling under my insurance a smarter move even if I have to pay my deductible when his limit could very easily be only 5k for damages?