cant see that from the picture, only really the the linkage, TPS and IAC can be seen from that pic.
So really what your saying is that the left throttle is a dummy and only provides air to the plenum. Nothing wrong with that, most ppl choose this same setup.
as long as both rocker cover hoses should be venting into the plenum, u can always pipe them both to a catch can, and have the breather going back to one of the throttles, doesnt really mattet which.