Restart Game only working on dedicated / listen without clients

Hi there, trying to figure out why it is not working as intended.

Following scenario is being tested on same system (computer):
From “HUD Menu” Iam casting to gamemode_custom and trying to run the “restart game” command in said gamemode.
It is working as intended on dedicated server (doesnt matter how many clients) and working on listen server, as long as there is no extra client (only host player). As soon as iam trying to call restart game with an additional client (as listen server), the command does not seem to do anything. All casts coming through though.

As Iam trying to do the same as above, but this time with 1 system for each player/client, it works.

Currently trying to implement some custom event to get around this. But I would like to understand why the restartgame cmd is doing nothing.

Any ideas why the restart game cmd isnt working in said scenario ?
Thx in advance