But...
We are trying to monitor only the uplink ports of Extreme switches park (all x440 - XOS 15.7.1.4).
Without the Port Elements Group, the Alarm "Link down" and "Link Up" detect the status of the ports and generate Alarms, but with the Port Elements Group on any port, generates no Alarm.
Netsight 6.2 here.
EDIT:
complementing ... during testing, the NetSight records the fall of the link in the syslog and trap