I know. I have even created a burrow for him, but his fav spot to hide in is under the bridge, but that's OK since the UVB reaches there as well.If he has the space that is in ambient temperature to retreat to that's still OK...that is the reason why Tom suggest a bigger enclosure. To make sure that he can regulate himself by walking around in and out from a higher temperature/basking area.
Basking area should be just a small part of his enclosure.
http://www.tortoiseforum.org/threads/ernie.136677/
Story with a happy ending...
Don't give up on him, your his best chance... but I do understand were your coming from and that I would be very pissed...
As Mark or Tom mentioned he has some growth lines...I wouldn't crossed him out just yet.