Sorry for my late reply, did not see your post here until now.
There are at least 2 ways to get MakeCode Arcade games to run on an arcade cabinet with a Raspberry Pi.
Either the firmware method on a RPi Zero, which you linked to above, which requires the games to be downloaded as UF2-files from the editor, or
Using McAirpos on a vanilla Linux installation or a retro games system, like RetroPie, Recalbox or Batocera on any Raspberry Pi model, presumeably also any SBC with the same ARM architecture:
Here, you still(I have some distant plans to support uf2) have to download the MakeCode Arcade games as .elf files, which you could get help generating from a MakeCode Arcade share link here:
Or, doing it manually yourself in the editor like this: