Ember DS.Errors troubleshooting on create form.

I have a basic create form setup which has validation on the name field. The save action for the form has a promise to gracefully hold the error:

    actions: {
        save: function(){

            var route = this;

            var createCampaign = this.store.createRecord("campaign", {

                code: this.get("code"),
                name: this.get("name"),
                description: this.get("description"),

            });

            this.set("code",""),
            this.set("name",""),
            this.set("description",""),

            // POST values to campaigns

            createCampaign.save().then(function(c){

                route.transitionToRoute("campaigns.view",c.id);

            }, function(errors){


            });
        }
    }

});

My defining attributes is:

    TM.Campaign = DS.Model.extend({
    name: DS.attr(),
    code: DS.attr(),
    description: DS.attr(),

});

I've read that by using a RESTAdapter, the ajaxError needs to be overwritten, so I've added the following:

ajaxError: function(jqXHR){

        var error = this._super(jqXHR);

        if(jqXHR && jqXHR.status === 422){

            var response = Ember.$.parseJSON(jqXHR.responseText);

            errors = {}

            if (response.errors){

                var jsonErrors = response.errors;

                Ember.keys(jsonErrors).forEach(function(key){
                    errors[Ember.String.camelize(key)] = jsonErrors[key]
                });

            }

            return new DS.InvalidError(errors)

        } else {

            return error

        }

    }

The response which is coming from the API is structured as:

    {

    "errors": {
        "name": [
            "The name field is required."
        ]
    }

}

But for some reason, whenever I try to display DS.Errors (using console.log(route.get("errors")), I get undefined. It's like Ember doesn't know that a validation error has appeared within the response.

I've also made sure that the response status comes back as 422 Unprocessable Entity. Can anyone see what I'm missing??