Yes, you could paralell two air motors. But you would either need some sort of valve to direct the airflow, or they both would be on at all time.

But theres one thing which I think most people have missed, I dont think Daniels after air motors to run his disc continously, but motors that will help him boost the speed just before impact.

When it comes to motors, he must be better of with a pair of motors from some air tools, and a regulator?