It's this simple*. If a person, or dealer, sends someone a gun that clearly has been misrepresented they should hold the buyer harmless. What that means is the seller should pay for all reasonable, direct costs associated with un-doing the transaction. This is the case regardless of whether the misrepresentation was known or a simple oversight. We know it's impossible that someone as brilliant as Galazan/Lou would have missed the problems with this gun, so we can only assume they were sloppy in their description. They should suffer for that sloppiness - no one else.

*I know it's that simple because it's how I behave. If I can do it, so can everyone and anyone else.