So it’s clear: the place is still viewable from the Roblox website, but it’s harder to discover as it’s hidden from most pages except the creator’s inventory. The only place of a game that will actively show is the Start Place. Attempting to join a place in a game will send the player to the Start Place, provided they have sufficient permission to access the game.
The above post explains how you can add a new place to your game which you can teleport to. If you want to create a new server that can’t be joined except through teleporting, ReservedServer is what you’re looking for. If you need data from another place, use DataStores (for player data and such) or TeleportData (for constants that, if changed, would not critically affect gameplay).