I know it's a pain, put I'd suggest mounting another scope that you know is good. Can't think of anything else offhand that would cause what you describe, assuming the smith fixed the mount. Wouldn't be surprised if the mount wasn't the real issue at all, despite the loose screw, depending on the type of mount. A collimater might reveal that without swapping scopes if you have one, but I've only used one a couple of times for bore-sighting while working in a store.
