It is probably not impossible, but it is a bit tricky. Look for example what I did in this rackspace to have controllers changing what they control at each variation:
Regarding what you seem trying to do, we could perhaps change the MIDI channel of your control surface (at the gig script level) such that GP would see different MIDI messages depenging from the channel. But, as @schamass mentioned, the sync will also be tricky. This very special use case will need to be addressed specifically.
But what you exactly want to do is still not very clear to me.
So let’s come back to the basic question:
A gig file could perhaps better illustrate what you plan to do.