Players turning into AIs
From Warzone Wiki
If enabled by the game creators, players can be replaced by a computer-controlled AI when they surrender or are booted.
If the AI ends up winning the game, the original player is credited with a win just as if they had won the game themselves. Similarly, if the AI player loses, the game counts as a loss for the original player.
Players can take back control from the AI by opening the game and clicking "Take over from AI". They can only do this a finite number of times per game. See the game's Settings panel to see how many times they can take back control.