All the European media are now reporting that what was found in the house was a torn-up sick leave certificate for the day of the crash, and evidence that he was being treated for an ongoing depressive illness, which he’d hidden from his employers. No evidence whatever of any religious motive.
In the USA, as a doctor, you would have to ground a pilot if you put he or she off work. Just giving someone a note, in my mind, is not good enough. I think this would put the physician in the mix of a lawsuit, no?