How customize pairing method to cast on Google cast android tv built-in, so cannot see or listing to another user either on the same network?

Question

Currently, i just try to customizing pairing method to cast to android tv chromecast built-in on my office. by default if we connect on the same network, all the device are listed before we cast. Also if we cast something, other user can see what we cast. how to customize the cast receiver to keep the private, like a gateway before casting. here is the example what i want :

1. user connect to the same network that android tv connected (as usually)
2. user scan code or go to something url to pair to the android tv
3. user only see the android tv that paired before and cannot see another android tv, either on the same network.

and here is the example of apps that was developed :

• https://www.youtube.com/watch?app=desktop&v=Piz20d2Wc8Y
• https://www.airwave.tv/3758/Chromecast-for-hotels

thanks in advance

I have tried to search the information, read the documentation and example of customizing cast receiver, web cast receiver. but i cannot catch the flow and which one is used to customize, how to customize. And there is no result The quick solution is creating vlan (but its not good idea imo). Can anyone explain the flow how to create like the working example as above ?