What about the rudder trim?
As the engine failure happened a long time before the approach could he have trimmed out the rudder force, and then not removed it – combine this (maybe) with a high approach speed and stress maybe resulting in confusion just above the runway (what’s it doing?) “forcing” him into applying full power?
Or
If he didn’t trim out the rudder holding it could cause tiredness and associated judgement error
Or
He may have trimmed it then removed the trim before starting the approach
I know my leg killed me after doing a join, hold and NDB approach on one engine (IRT)