New Post: Possible to register the same ViewModel with Different names?

I figured out a solution to get the current FlowDocumentViewModel for the corresponding SpokenViewModel for a NonSharedobject. After the TabItem is added to the Collection it causes a OnItemsChanged(NotifyCollectionChangedEventArgs e) event. And here is where I search for the Composite View to obtain the the Model:

protected override void OnItemsChanged(NotifyCollectionChangedEventArgs e)
{
    base.OnItemsChanged(e);

    .
    ..
    ...
    
        if (e.Action == NotifyCollectionChangedAction.Add && SelectNewTabOnCreate)
        {
            SpokenTabItem tabItem = (SpokenTabItem)this.ItemContainerGenerator.ContainerFromItem(e.NewItems[e.NewItems.Count - 1]);
            SelectedItem = tabItem;

            SpokenTabPanel itemsHost = Helper.FindVirtualizingTabPanel(this);
            if (itemsHost != null)
            {
                itemsHost.MakeVisible(tabItem, Rect.Empty);
                SelectedReferenceState selectedReferenceState = tabItem.SelectedReferenceState;
                selectedReferenceState.contentControl = LogicalTreeHelper.FindLogicalNode(tabItem, "FlowDocumentDetails") as ContentControl;
                if (selectedReferenceState.contentControl != null)
                {
                    selectedReferenceState.flowDocumentReader = FindVisualChild<FlowDocumentReader>(selectedReferenceState.contentControl);
                    selectedReferenceState.flowDocumentFilter = Parameters.FlowDocumentChangedEvent;

                    IEventAggregator eventAggregator = ServiceLocator.Current.GetInstance<IEventAggregator>();
                    eventAggregator.GetEvent<FlowDocumentChangedEvent>().Publish(selectedReferenceState);
                }
            }

            tabItem.Focus();
        }
    ...
    ..
    .
}

..then I execute an Event for the SpokenViewModel and update the reference to the FlowDocumentViewModel:

private void OnFlowDocumentChangedEvent(SelectedReferenceState parameter)
{
    .
    ..
    ...
    
        FlowDocumentView myFlowDocumentView = TreeHelper.FindVisualChild<FlowDocumentView>(parameter.contentControl);
        this.flowDocumentViewModel = myFlowDocumentView.ViewModel;
        this.SelectedReferenceState = parameter;
        this.flowDocumentViewModel.ReadReference(selectedReferenceState);

    ...
    ..
    .
}

:) Any suggestion?