Use the service config for consintency.

playbooks/edx-east/edx_service.yml

@@ -201,7 +201,7 @@
         instance_type: "{{ service_config.instance_type }}"
         instance_profile_name: "{{ instance_profile_name }}"
         volumes: "{{ service_config.volumes }}"
-        instance_monitoring: "{{ detailed_monitoring }}"
+        instance_monitoring: "{{ service_config.detailed_monitoring }}"
       when: auto_scaling_service
 
       #