Absalom
SWCA Member, Absent Comrade
i've got some good deals off of GB because dealers didn't know what they had
I really don't think this has anything to do with "not knowing what they had"; this is simply bizarre. Looking through their various and extensive online offerings, this is not a pawnshop, but a professional and competent gun business that knows guns, and there is no reasonable explanation for the listing, down to a specific dash model number that apparently came out of nowhere, of the wrong gun.
If I were the OP, even if I decided to keep the gun, I'd be on the phone with the manager just trying to nail down what happened in any case. If there is an innocent explanation, they would want to know too.