'cut him off' is an expression meaning, in this context, that the insurance company isn't going to pay for the car hijackings. I guess that 'to cut off' is to remove oneself from an obligation or a committment. I have heard it used when parents stop supporting their children. I.e. Mr and Mrs Smith have cut off their only son because at the age of 25 they decided he needed to support himself. Is this clear? I suppose I could try in Spanish if you want.