This is exactly the diagnosis by Honda Cavalry for my ex Civic, remember?
Apart from this, I tried everything on it. I guess this is the only thing that's left out. Check out how much kabuli transmission would cost from Bilal Ganj.
The only doubt in my mind is that its an auto - and automatic doesn't get the rough treatment we usually give to manual transmissions, i-e sudden release of clutch after revving the car to 4000 RPM.