It is not what I (or you) think, it is what is factual and true. But I would think Lending Tree knows what their study is about more than you (or me.) Did you ignore all the quotes I put in?
But to answer your question, the reason I would think (aside from Lending tree told me so) they were using data from insurance quotes is because people have to report how many accidents they have, and they also say what kind of car they drive when they request a quote. But they don't say what kind of car they were driving when they were in an accident, only the make of the car they currently want insurance for, so really meaningless data without even correlation.
I would never think the data was derived from auto repair quotes because that would be even more meaningless data, and no one ever mentioned this was the source (other than you).