Mental illness
While I can only comment on my limited experience in three flag carriers.
My first paid three months full salary on sick leave then after a reduced income sacked you after a further three months.
Loss of license insurance paid only 10% of sum insured for mental problems.
These were the days when being labeled a "nutter" was one's fate.
I lost my license on mental health grounds in 1996. My company paid my salary for nearly two years before taking my medical away from me whereby I was transferred to an invalidity pension which was paid out of the (separate) pension fund.
It was in the companies financial interest to permanently remove my class 1 medical and the examining doctor was the company doctor.
In Hindsight it was possibly aerotoxic syndrome as we had a spate of pilots with similar mental health problems. If our illnesses had been classed as work related then the company would have been financially responsible.
Fortunately I only suffered severely from the Black Dog for seven years.....
Hopefully we will discover that it had nothing to do with mental illness as such but perhaps a seizure ...which has happened in flight to colleagues.
IMHO the security measures will have a sensible re hash but it's too late to redeem the flight engineer.
In the UK, hospital mental committal is only available to a male if he has seriously attempted suicide on three occasions. It is time to come out of the stone age.