How to connect arduino remotes via wifi isolated from other systems?

Question

linux

It is necessary to implement a refereeing system with wireless consoles, I don’t know how to isolate the consoles from different mats from each other.
There is Raspberry, it is responsible for displaying the image on an external monitor + communicating with the server (getting categories and participants). You need to somehow connect 5 wireless remotes to it. The task of the consoles is to send points (1, 2, 3). Raspberry's main Wifi is used to communicate with the server. Also, a 3.5 inch monitor with a sensor (category control) and buttons (time control) is connected to the raspberry.
There is an option to connect an Arduino with a WIFI module to the raspberry via USB. Connect 5 other remotes to this Wifi module. What module do you recommend?
The question is different. If there are about 5-9 carpets in the hall, how can I isolate the consoles from each other? Help, please, with advice and links to articles.