To my knowledge there was only one person selling fake Jerry's. I was unfortunate to buy 2 decks from him but luckily got my money back. So now I have my money and 2 fake decks.
You could also look into mnemonics to remember multiple things. I don't think you would need it for only 2 cards but when having to remember many things it helps. I would just say them over and over in your head through the trick.