What are you going to protect yourself from? If his (dude that hit you) insurance company says our driver says it was your fault… then you call your insurance company and tell them the story and tell them to not pay out a claim on his car… then both the companies will settle it out in court if need be.
Before you call your insurance wait to hear from his. If they dont contact you in like 2 days, then call your insurance, tell them what happened but also tell them that you DO NOT want to open a claim under your insurance, you are just calling them to inform them about the situation.
I would just wait and see what they say, if they give you trouble, then call your insurance company.
You could call his insurance company, but when he calls in and reports a claim, they ask him for jph’s information. Then they are required to contact jph for a statement. Some people don’t wait for them to call… which is fine, you can contact them, but they should contact you automatically.