The orbits given here for Motavia and Palma also contradicts later statements that the two planets pass each other in their orbits.
Yeah, that later Sega explanation that Mota and Palma didn't switched orbits after all, it's hard to fit here. Look:
These are the orbits from PSI manual. It looks like the problem is more than the eliptical orbit of Motabia. In PSIV Parma was the one with the elliptical orbit. (They really switched).
The only explanation for this "mess" is the explosion of Parma or simply a Retcon in PSI story.