[Fa11ou7]

I've been working the google search as hard as I can and I am not able to come up with a solution that meets my needs so I'm asking for your help in my search.
 
Setup;
I run a simulation lab for a nursing school where we have a control room with 3 stations that allow us to run 3 simultaneous simulations at the same time. Ever since I have worked here we have used wired sennheiser headphones (sometimes up to 5 HP) on a splitter connected to the PC at each station. The wires from multiple headphones are a pain in the rear, just about everything else is wireless so I would love to swap out the wired headphones at each station for a wireless setup. 
 
Needs;
* A transmitter for each station that allows for either: 
A) 4-6 wireless headphones per station
or 
B) minimum 2 wireless headphones and a headphone out plug that I can put a 1/8" splitter on with wired HPs for when we have more than 2 people listening at said station/transmitter
* Capability for 3 of the same systems to run at the same time
* (optional) Capability for headphones to switch between transmitters
* (optional) Rechargable would be nice
* (optional) Headphone out plug in case wireless has problems
 - audio quality is not a priority, as long as we can hear the normal talking volume of the students that we are observing without static or delay it is fine
 
 
Possible problems;
* most wireless headphones that I have looked at operate on a certain frequency so you can't have 3 transmitters in the same room
* Most of the systems don't specify how many headphones you can connect to them (must have minimum of 2 HP, see above)
 
 
The best solution that I have found so far is this Kickstarter system that is supposed to  come out sometime next year;
https://www.kickstarter.com/projects/ekkowifi/hub-by-ekko-the-first-hi-fi-wi-fi-hub-for-headphon
 
Thanks for any help you can give me!