I reccomend you get your own expert mechanic to look at the car and all the parts involved to determine what happened and who is responsible. Also, take a look at your contract with the body shop. Did they warrant the work they performed? Did they agree to use new OEM parts or after market parts (i.e. the after market clamps)? f your mechanic determines the hoses came off because of faulty after market clamps or any other defective work performed by the body shop, then the body shop should pay to replace the transmission. The terms of your agreement with the body shop could be controlling, so I recommend you carefully read those terms before taking any further action.