Does this expand an already existing service

No

Link to a game or software

https://store.steampowered.com/app/261550/Mount__Blade_II_Bannerlord/

Links for the download

https://steamdb.info/app/1863440/depots/

Links for the install docs

https://forums.taleworlds.com/index.php?threads/1-2-hosting-dedicated-servers-on-linux.460939/

There is currently an egg for this game as shown here: #2519

Unfortunately, the new 1.2.x update for the game has broken the egg causing it to hang on startup (egg link: https://github.com/parkervcp/eggs/tree/master/game_eggs/steamcmd_servers/mount_blade_II_bannerlord), I believe the reason is that it's running in wine, but I cannot be sure. I found a forum post with TaleWorlds claiming it's possible to run it natively on Linux with no need for Wine (install docs).

If a working egg can be created that'd be great.

Please excuse my ignorance with the technical side of things.