Found this ... does it help?
"... To assign a MIDI CC message to the Rotary parameter, you must have a controller on your keyboard that can be assigned to send MIDI CC# 75 - 87.
You can then assign one of these parameters to the Rotary parameter, depending on the Organ instrument sound you are using"
Every instrument, every voice, every sound in nature ... these are are all my private tutors ... 24/7 for free, and all I have to do is listen.