ng-model not attaching to controller $scope when inserting modal form from Django - angularjs

Question

I'm serving a form from Django into an angular-ui-bootstrap modal using the template property:
function openFinderModal() {
var modalInstance = $modal.open({
template: vm.modalTemplate,
});
The relevant part of the modal template served from a form view:
<div class="modal-body" >
<form ng-controller="ServiceFinderModalController">
{% csrf_token %}
{{ form }}
</form>
</div>
I'm then using django-angular to create an ng-model on each form field (see the docs), corresponding to my simple form below:
class ServiceSelectionForm(NgModelFormMixin, NgForm):
service_0 = forms.BooleanField()
However, when I attempt to access this form field from $scope I get undefined.
function ServiceFinderModalController($scope) {
console.log($scope.service_0);
}
I've inspected the source of the page and it seems as though it should work (see second last line):
<form ng-controller="ServiceFinderModalController" class="ng-pristine ng-valid ng-scope">
<input type="hidden" name="csrfmiddlewaretoken" value="dkH6aiHyIqqkJlN5xAbiYaX0c37tXb9U">
<ul class="djng-form-errors ng-hide" ng-show="U2VydmljZVNlbGVjdGlvbkZvcm0.$pristine">
<li ng-show="U2VydmljZVNlbGVjdGlvbkZvcm0.$message" class="invalid ng-binding ng-hide" ng-bind="U2VydmljZVNlbGVjdGlvbkZvcm0.$message"></li>
</ul>
<ul class="djng-form-errors ng-hide" ng-show="U2VydmljZVNlbGVjdGlvbkZvcm0.$dirty"></ul>
<label for="id_service_0">Test 2</label>
<ul class="djng-field-errors ng-hide" ng-show="U2VydmljZVNlbGVjdGlvbkZvcm0.service_0.$pristine">
<li ng-show="U2VydmljZVNlbGVjdGlvbkZvcm0.service_0.$message" class="invalid ng-binding ng-hide" ng-bind="U2VydmljZVNlbGVjdGlvbkZvcm0.service_0.$message"></li>
</ul>
<ul class="djng-field-errors ng-hide" ng-show="U2VydmljZVNlbGVjdGlvbkZvcm0.service_0.$dirty"></ul>
<input id="id_service_0" name="service_0" ng-model="service_0" type="checkbox" class="ng-pristine ng-untouched ng-valid ng-empty">
</form>
I've tried doing things like $scope.$digest() but get [$rootScope:inprog] errors.
UPDATE
The $scope becomes aware of this field once it has been toggled. Now I just need to figure out a way to do this from the get go...