Paid for a skill that got automated overnight, that stings.

Twenty minutes before the glue wheel jammed? That thing was doomed from the start.

Man, I don't know about all that. People have been spraying contact cleaner on stiff helicals for decades and I've never once seen it eat a grease seal, so maybe that Nikon was already dried out and cracking before you ever touched it. A $60 repair also sounds like somebody charging you shop rates for a five minute job, which is a whole separate scam. Not saying pulling the mount is wrong, but 40 extra minutes on every lens sounds like a lot of work to fix a problem that might not even exist.