By psychiatric test they mean psychological profiling. It is not fool proof. Moreover he has been in the business of aviation for 30 odd years and have logged 17000 hours. Psychological tests are very subjective and gives out very generalised opinions. Apart from Defence forces I doubt if it is being used anywhere else. The report (31 year old) is no reflection of pilots health as of today.
In my opinion it was a very rare occasion when small small issues aligned to gradually take the pilot into this mess. Ego, complacency, gap in flying, empty sky, over confidence and simply oversight made them high and hot. Thereafter they tried to catch up with it and in rush of things the two pilots went out of synchronisation. The number of parameters that they were juggling were simply beyond their cognitive abilities. Still seeing the runway straight ahead they thought they can salvage the approach.
Things would have worked out (in pilots opinion) but because of one aspect, gear, which he thought was down. I think the pilot all the time thought that the gear was down. Perhaps it could be on the back of his mind that in case they land too long he will go round. Moreover human is capable of doing something which escapes explanation. I feel sad for the Pilot monitoring who could not muster enough courage to challenge the pilot. I think it is an organisational issue.