Ram tranny problems

Yeah the 1200 bucks is for a bench rebiuld if it take the trans out my self. But the valve body needs replaced too? I can understand replacing everything if the tranny completely exploded. I don't know maybe you should like I said before sometimes its the little stuff that gets you. Fishy what's engaged in reverse in that mechanical sequence? I'm just pushing buttons in my head wondering why everything else is still working.