The aircraft manufacturer’s job card for a turbulence inspection specified a general visual inspection of the fuselage, stabilisers and wings with more detailed inspections if any anomalies were found.
How does a pilot inspection identify a problem with the horizontal stabiliser and an engineering inspection does not. The QAR also confirmed a 3.3g load with control disconnect which was outside the aircraft limits for weight! Does that not warrant a further investigation beyond the 'turbulence inspection'.
It appears the initial defect entry(control disconnect) may have been understated and it was only after further queries by engineering that they mentioned moderate turbulence.
I am sorry, but scratching at the surface of this reveals some fundamental errors by ground and air crew.