That's a very bold assertion. I don't think they would push a driver out that recklessly just to stop one hardware hack. Besides, this was posted within a few days of him posting on the nVidia forums and you said yourself, the issues you had with the card are a few months in.

Even if they knew about it before hand, it's not like a critical vulnerability or something; just an interesting modification to hardware (rarely how intrusions happen) that very few people know to implement correctly and fewer still who would want to do to their cards.