Traitor aims to be a game similar to Among Us. I've never actually played Among Us though, so your mileage may vary. :)
The game provides nodes and mechanics for building and playing 'levels', but has no mapgen, relying entirely on user generated content for the map. A spawn hub should be built around 0,0,0. New players who haven't yet completed the tutorial or played a level will spawn at -30, 0, 12. Currently both spawn locations are hard-coded, but they will be configurable later.
To create a new world/server grant youself free and fly, teleport to 0,0,0 and use world edit to create a platform for new players to spawn onto. You may want to build walls around the platform so people can't walk off the edge and fall forever.