I've had this happened to me, except it was at a Firestone. Call corporate if you haven't already and tell them to replace your wheel (not repair) & ask for a full refund. They will likely ask to mount the tire to the new wheel themselves. Go elsewhere and return the damaged wheel when you're done. Look for a shop that offers leverless/touchless mounting. Tire Rack has a list of shops that have that equipment or just look for a place that sells custom wheels. They usually have the best equipment.
http://www.tirerack.com/installer/index.jsp
just enter your zip in the upper right and it will list shops near you. Then click "select/more info" and it will list the eqiupment they use.