Hard to tell for sure since I'm not an expert in any of the Williams games but they sure felt ported.
I think this is a given. Authenticity doesn't appear to even have been part of the equation.
The cart, though if you look at the connector, seems to have a/v outs. Not a pinout. That would mean that all it really is is a 4 in one style game designed for that cab... though not sure where it would be getting power from. Maybe there is also a small PCB that plugs into that slot.
My prediction as to what that is (having not seen one yet):
The 3 pin doohickies are Male RCA style connectors, one each for composite video, left and right audio. Maybe only mono audio and one used for 5v power.
The card slot probably just connects up the controls (JAMMA-like, if you will).
If this proves to be the case, it's actually an interesting design. Keeps the cabinet almost completely "generic" from a hardware standpoint. Means you could even make an MP3 player module for JukeBox purposes and use the controls to run it. Not that anyone would want to, but it seems possible.
It also could mean that this may be the first of many to come out. Same cab set-up, but new graphics and "cartridge". Who's next, Taito?
RandyT