Yes, I believe that Polgar created this effect as well as finding his check with contact mindreading.
While I own an original signed copy of the Meyer manuscript, I bought Bev's routine for several reasons - 1) Bev is a professional performer, 2) he had done the effect hundreds of times, 3) I've known Bev for decades and know him to be a clever guy so I knew, given his cleverness and experience, that I would be receiving something that had been refined to a high degree and that Bev would not hold back anything he deemed important to the presentation 4) I knew his manuscript would contain the essence of his performing experience which means the presentation and suggested timing of the effect - how the various parts all fit together to make a strong presentation.
The "real" secrets of magic are in the timing and presentation, not the physical means of producing the effect. In this case the Magic Square and mnemonic techniques are readily available for next to nothing in the literature and on the Internet. What I wanted was Bev's experience.
The "difference" of $68 that you point out is nothing to someone looking for professional-level performing material. Indeed, the material is quite cheap to a knowledgeable professional performer.
I also knew that once I had this worked up I would have something that was commercial, impressive, and that few others would take the time to learn. It's good to have material like that.