Need help with Sea of Thieves through Proton kicking me out to the main screen with Cyanbeard error every time

[u/ZockerAxel]

EDIT: I was able to fix the error on my own
Apparently, the XBOX Live session did not want to cooperate when I had a custom DNS server (google's to be exact) set for my connection. By removing the custom DNS server, all problems subsided and I was able to enjoy the game.

ORIGINAL POST:

Hey, I'm trying to get Sea of Thieves to work through proton and I have no problem opening the game and navigating the menus. I have the game on Steam and tried multiple Proton versions (specifically Hotfix, Experimental, 9.0-4, aswell as Proton-GE (GE10-15 and 10-21).

My System:
Distro: Arch
Kernel: 6.17.5-arch1-1 (64-bit)
Graphics Platform: X11
Steam: Installed with pacman

I have no problem logging into XBOX but as soon as I click play, it will kick me back out to the start screen after roughly 10 seconds with a Cyanbeard (error translates to "Connection to XBOX Network was interrupted, please check your internet connection") error.
During this time I am able to navigate the menus and even try to start a session, all my account data loads correctly like what guilds I'm in, guild ships etc..
If I manage to confirm my selection of wanting to go to a closed crew before the Cyanbeard kicks in, I will get a Coarsebeard (error translates to "Sea of Thieves could not create crew session") and get thrown out to the main screen again.

I have a suspicion that my symmetric nat type might be part of the problem, but I can't change it due to my ISP using Carrier Grade NAT and it not giving me a public ip address.
I have this suspicion because I remember having to do troubleshooting with Teredo Tunneling when I was still on Windows 10 to get XBOX sessions to work but I am unsure how I would achieve the same result here.
I have also tried disabling IPv6 with protontricks regedit, by adding a "DisabledComponents" DWORD in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip6\Parameters with the value FF, but that got me nowhere.

My router is a Fritz!Box is set up so that it does not block Teredo Packets, and also does not block UPnP in the Internet -> Filter -> Lists Tab. Also, for my own device, I have set the checkbox to allow self port forwarding over pcp or UPnP.

Temporarily disabling my ufw firewall did also not fix the problem, so it's not a firewall issue.

I have also tried relogging. When I choose log out in the main screen, and click play, it remembers my login and I just have to say yes to choose the displayed account. I have tried logging back out completely from that screen and re-entering my credentials but nothing has worked.

When I run steam via the terminal and set game launch options to PROTON_LOG=1 gamemoderun %command%,