You are right. I read on some forums that Guido himself confirmed that the new VST version is the same engine used in the Mojo and probably the Gemini module as you said.

I am not sure if I like the built-in Leslie effects in the new version better than the old version. Then again I didn't tweak anything. Still, right out of the box I like the sounds and GUI of the discontinued B4 II by NI. Probably more so than the piano, the tone-wheel organ combined with the factor of Leslie effects can be very very complex to reproduce.