Great job as always Willie!
That MSI Ms. Pac-Man looks like Namco's NES version with better colors. Sounds like that game too. Kind of puzzling that they would release that game as a standalone plug and play... it wasn't good in 1993 when it was released and it's not good now.
I believe it is the NES version they used. This, unfortunately seems to be a pattern for MSI. Make a PnP that looks like one Jakks Pacific made in the past that had multiple games on it, but only put one, inferior NES/Famicom version on it instead and charge full price. They did the same thing with their 2016 Space Invaders model.
What's sad, is on their website, they even used pictures of the Jakks Pacific version of Ms. Pac-Man to advertise their own product. Very misleading.