1999 Audi A6 Valve Repair

My mechanic put a new timing belt on and set it at the wrong setting. Should have be 1 and he set it at 2 or visa versa. Anyway, the valves were bent and he is is the process of repairing it. Has been in the shop for over 3 weeks. My question is: When I had to replace the battery, they had to do it at the dealership because the computer had to be reset. Can my mechanic do this? Or, is he going to have to have someone at the Audi dealership do it.

Thanks for your help.