How to reset TabNavigator when user logs out (from other screen)

This should work in most cases:

componentWillReceiveProps(nextProps) {
    if ( nextProps.token == undefined || _.isNil(nextProps.token) ) {

        let action = NavigationActions.reset({
            index: 0,
            key: null,
            actions: [
                NavigationActions.navigate({routeName: 'Auth'})
            ]
        });

        nextProps.navigation.dispatch(action);
    }
    ...
}

Or try by enhancing your navigator with custom action:

const changeAppNavigator = Navigator => {
   const router = Navigator.router;

   const defaultGetStateForAction = router.getStateForAction;

   router.getStateForAction = (action, state) => {
       if (state && action.type === "RESET_TO_AUTH") {
          let payLoad = {
              index: 0,
              key: null,
              actions: [NavigationActions.navigate({routeName: "AuthStackNavigator"})]
          };

          return defaultGetStateForAction(NavigationActions.reset(payLoad), state);
          // or this might work for you, not sure:
          // return defaultGetStateForAction(NavigationActions.init(), state)
       }
       return defaultGetStateForAction(action, state);
  };

  return Navigator;
};

const screens = { ... }

RootTabNavigator = changeAppNavigator(TabNavigator(screens, {
  initialRouteName: ...,
  ...
}));

Then in your Menuo Screen do:

componentWillReceiveProps(nextProps) {
    if ( nextProps.token == undefined || _.isNil(nextProps.token) ) {

        nextProps.navigation.dispatch({type: "RESET_TO_AUTH"});
    ...