OK, so I picked up the frame tonight. No charge. I think the mechanic might have been exaggerating when he said they got the shell "red hot." The plastic derailleur cable router was a bit melted on the metal cup side, but the paint wasn't bubbled. They too used impact wrenches on it for over an hour.
One thing I couldn't understand about the Sheldon Brown method was the insertion of a nut inside the bottom bracket to get the cup out. I still have the BB itself still in the way. Can't get the drive side out because the plastic cup is stripped and can't get the metal cup on the non-drive side out because it is seized into the frame.
I'm also open to other hairbrained ideas, but I think both jbains and I need to consider if the juice is going to be worth the sqeeze.