Personally I would cooperate as long as her policy says they are entitled to cell phone records in the event the car was stolen, but if not, and no court order, I would say no. They work for you. Expect that. Even if a car is left unlocked, that does not imply permission to steal it. I assume your daughter was not involved, but if the insurance company is hinting that she did, or she actually did have a part... either way, why would you help them? This is not legal advice, just my opinion.
It goes both ways. If she doesn't want to cooperate, thats her right, but then again, the insurance has the right not to pay either if they suspect fraud.