I want to play custom theater in a single player. But when the level is loaded, the squad selection list is empty and the start button is not active. How to fix it? I tried different theaters, the problem is the same everywhere.

This is how I start the game:
1) Downloading the theater from Steam.

2) I edited "default_server_push.cfg" adding there:
"mp_theater_override" "theater_thearmoryexpanded8p_default"

3) When entering the main menu, I enter through the console:
mp_theater_override "theater_thearmoryexpanded8p_default"

4)Then I load the map for the singleplayer, I enter through the console:
map mapname push

What could be the cause of this problem? The squad selection menu is empty and I cannot start the game.