Backbone.Marionette CollectionView / CompositeView rendering

This question is a continuation of this related issue .

Taking Derick's advice, I now have the data in the correct form. those. I have a set of objects Department, each of which has a collection Users.

Following Derick's advice again, I'm trying to do CollectionView CompositeView

My collection view is as follows

class UserListView extends Backbone.Marionette.CollectionView
    itemView: UserCompositeView
    id: "user-list"  

    appendHtml: (collectionView, itemView, index) =>
      itemModel = @collection.at(index)
      itemView = new UserCompositeView
        model: itemModel 
        collection: itemModel.get("users")

      collectionView.$el.append itemView.el

and mine Composite Viewlooks like this:

  class UserCompositeView extends Backbone.Marionette.CompositeView
    itemView: UserItemView
    itemViewContainer: '#users'

If I do not override the appendHtml method, it displays the view, but it only displays the properties of the model Department. It does not display a collection Users.

appendHtml CollectionView, ( Department) Users, Marionette bindTo , 'on'.

?