In my further preparations of a tour in September, I stumbled upon a website about a "basecamp" on the Panixerpass. The hut is small and reservations can't be made, which means that quite a few people camp out there. Apparently that lead to some frustration and a "basecamp" was attempted. You could make reservations for a tent and there was a big dome tent which served as a community room.
https://www.basecamp-panixerpass.ch/
In 2024 this was an attempt, but it has been decided to NOT open for summer 2025. Reason being given is to protect the sensitive nature at the pass.