The problem is that you are mixing jQuery like logic with angular logic here : manipulating the dom 'by hand' is rarely a good solution.
The problem here is that your newly added binding has not been compiled by angularjs = it has not been indexed as a directive that should be watched for and updated when scope changes.
Either you try a more angular way, for example using ng-hide or ng-repeat directive to display your content according to the controllers $scope (or another custom directive), or you try to $compile your newly added directive ( but this is bad ) : https://docs.angularjs.org/api/ng/service/$compile .
Maybe try in your controller : $scope.$compile( div );
Not sure of the syntax though. Maybe you would need to write
<span ng-bind="..."></span>
instead of
{{ ... }}
to make it work.