I can't see any sense, reason or likelyhood of creating a "gas chamber" style room either. A room large enough to accomodate large unit movements in and out, with the air-tightness required, evacuation of gas afterwards for health and safety, the labour and cycle times, the sheer waste of gas etc etc ..... How would they close/plug the units when filled optimally would be my first question?
Maybe something has been lost in translation??? There are IGU line inline gas chambers, which is certainly possible on modern high end lines in high investment factories. Units stay on the line, and pass through a gas chamber individually, being then pressed and sealed immeadiately. This is the only real system that has no need for plugs or other usually visual forms of cavity penetration. Maybe someone has has misunderstood "gas chamber", and came up with a 'room' theory when they told you? Looking at the photos on the website, I see what looks like two IGU lines. One is a standard press Willian (yellow+grey), and the other blue coloured machine that looks like a line and has an offline argon filling station right behind it.(silver cannister, red pipes for probe and sniffers). It could be an online gas chamber somewhere there, with a manual fill beside it. Can't really tell. Maybe they have more equipment not shown.
It's a wacky first idea anyway.
The other real questions relating to this thread as well as gas mixture evidence :-
Are cut-down super spacer products like these gas filled in any meaningful way or reliable way?
Do they retain gas with sealant depths well below manufacturer's guidelines, and without primary seals?