Adding params to route model breaks createRecord

Since adding a param to our route's model, we can no longer add new items in our Documents ArrayController:

Old Route:

model: function(params) { 
        return this.store.find('document');
}

New Route:

queryParams: {
    owner: {
        refreshModel: true
    }
},
model: function(params) { 
        var ownerID = this.get('ownerID')
        return this.store.find('document', {owner : ownerID});
}

ArrayController:

actions: {
      addItem: function() {
      this.store.createRecord('document');
}

The code still loads the documents, but when the addItem action is called, the newly created record is not added to the ArrayController's content. In the old code, clicking addItem immediately showed a new document on screen. I have confirmed that the server is returning an array, so am not sure why new documents can no longer be added. Any help would be greatly appreciated.