This will map the CC to poly aftertouch, but it will generate 128 aftertouch messages (one per note) per controller event as you move the controller, so not sure how feasible this will be given the speed of MIDI (hardware).
I think the fundamental issue is that poly aftertouch is on a per channel+note basis and controllers operate only on a per channel basis. I think the only way of thinning this would be to monitor which notes where being used and only issue the aftertouch messages for those notes. I'm just thinking out loud. This sort of logic isn't something the Stream Byter would cater for right now.