Unless Nintendo helped finance the development of the game or they have some sort of exclusive contract, timed or otherwise, the only technical thing keeping it off other platforms is the ability to adapt a user interface other than the Wii Remote.
It's safe to say the first didn't happen, and the second is also highly unlikely as Nintendo doesn't "buy" exclusives from 3rd party developers because they don't have to. They have their own catalog of Nintendo developed exclusives representing their hardware platform.
Naturally, with the PS Move, the user interface is a non-issue, so the only question is whether DIsney estimates the returns on a PS3 port worth the additional development and release costs.
If they went with a fairly straightforward upscaled port (as seen for unported Nintendo Wii titles being played via emulator on PC with good results), with revised on screen menus to take advantage of the higher resolution, and another fairly straightforward control interface coversion, it wouldn't take much effort.
So, minimal risk involved. It's more of an issue of if demand for a PS3 port justifies the cost of a re-release (which would involve marketing the game again to the new audience).
