Trigger Condition

private insideTrigger = { alive _x && isPlayer _x && side _x != sideLogic } count thisList;
private alivePlayers   = { alive _x && side _x != sideLogic } count allPlayers;

if (insideTrigger == alivePlayers) then {
    "EveryoneWon" call BIS_fnc_endMissionServer;
};