Gameflow Server/Lobby Setup

hey, i need some help/suggestion regarding figuring out a working setup for my game.
im trying to recreate a multiplayer system like in the Monster Hunter Games.

what i currently got:
a custom master server “GitHub - RyroNZ/UE4MasterServer: This is a plugin for Unreal Engine 4 that adds server registration, deregistration etc with a master server.”.
i’m starting X LobbyServer on my Server.

Player Starts Game, selects a lobby server and joins the lobby.
there he can talk to an npc and selects a quest he wants to host.(IP/Port are added to a variable in the queststruct)
optional: other player can select a quest board, where they can see all hosted quests and can join them.

player host initates the quest start, quest host loads the new level with the “listen” parameter.
with a delay “right now 3 seconds” the other members who joined the quest join the ip/port from the queststruct variable via the command “open IP:Port”

hope its understandable. is that a “OK” setup or am i doing something fundamentally wrong?

i’m also thinking about the possibility to let everyone create a new lobby server, whichs starts a dedicated server in the background.

i made a quick an dirty flowchart.

i also still need to figure out a way to get a connection from the lobby server to the sessions created my the players when they start a quest.