Lets be clear on one thing here as there are no parallels with the above.
United DID NOT miss or overlook an AD. They only half implemented it. Yes we should perhaps wait for a proper explanation however it is incredibly serious that the AD was detected, scheduled to be performed within the allowable time frame. yet not fully embodied.
There are a number of failures there which are a cause for serious concern.
If this was simply an AD oversight issue I would have fewer problems with events.