According to an official statement on Ryujinx's Discord server, developer gdkchan was contacted by Nintendo and they were offered an agreement to stop working on the emulator project, and while the agreement wasn't confirmed yet, the organization has been entirely removed.
kyun.host is mullvad-like insofar as your account is identified by a random account ID and they dont necessarily have an email etc on you (you can provide one so they can contact you if you want but that's optional). Have not used their services myself but I'm aware of them.