-If we manage to implement the multi-sig with multiple trusted members, then even if I go missing 1 hour after that it does not matter. The remaining members can run the service as if it never happened, so the service can continue with or without me
Alright, so everyone can setup a front end (whose source code, as I've read, you'll publish at some point) and connect to some backend that is hosted by the trusted members?
So since he said it's true, this means we can run this thing in the same fashion Tor exit node. Therefore, you should take exactly the same precautions as you would when you run a Tor exit node - use ISPs that are Tor-friendly, make sure you have lawyers and a good legal team, use hosting providers and datacenters that are OK with Tor traffic, and etc.
Just like how some countries try to charge Tor node operators with shady darknet actions that its users do, so these countries will try to charge those who host decentralized mixer frontends and backends, so everyone make sure you guys are not hosting them in countries hostile to mixers, such as the USA.