lazide

Okay so I knew it was the rear shaft seal, took it into local mechanic shop, drove twenty miles home, next day checking fluids and found NO tranny fluid, empty notta zip zero fluid. So I put fluid in, take for a spin and low and behold its still leaking!! During the obligatory phone call to this "mechanic", I was told that the shaft was scarred and that the bushing it fits into was probably bad and he would gladly rebuild the back end of my tranny for "not a cheap" price. Sorry about the history, but my feelings are is that he just did not seat the seal or damaged it somehow installing it, (even if he did install one). Has anybody heard of the rear "bushing" (I think its a bearing anyway) causing the tranny to leak profusely out the rear of the tranny? Or would have the short trip with no fluid cause damage that would cause leak? I know no fluid can cause internal damage but tranny seems fine other then leak.