The OG Devo7s allowed you to assign the bind code and could easily let multiple TX control a single receiver. The problem with that is which radio has priority. I would take a guess that proximity to the receiver would take control.
So if you are wondering what I think you are about maybe a long range experiment where you send the air craft off in a direction out of its range and have the next radio in the chain take over control I think it can be done with the Devo 7's. I have not seen in OTX anything that allows the user to create or assign a specific code like on the Devo 7.