[Petra-Kathi]

... I don't know if the device acting as the hotspot also participates/communicates on the network it creates.

Yes, that's a point. But even if not: It might be an interesting idea to complement the tablets with a very small addtional autostart device (like a headless Raspberry Pi, or maybe even an ESP32, running for hours on a small powerbank) that just provides such a net as hotspot. This would make the complete setup self-contained.

Cheers,
Petra