I would bet that if you search the bottom of the breech, water table, and the underlug, you will either find Belgian proofs or no proofs at all. Many Belgian and American-made shotguns were sold as private-labeled guns to be sold through hardware stores and mail order, and were named to sound just like the famous brand names. I once handled a Belgian shotgun that was marked Purdy (as opposed to Purdey, the high-dollar British firearms maker).
Never try to educate someone who resists knowledge at all costs.
But what do I know?