Good point,
QFandlovinIT, Australian examples of "garbage in = garbage out (ie. people who had previously been rejects, but were taken on in desperation) causing failure of the airlines that employed them, are
Ansett,
East-West,
Australian aka TAA, and
IPEC...... RIP the lot of them.
So was the alleged defect entered in the Aircraft Log Book?
If so, it would be easily traceable.
...it was the A system supply line being found disconnected during the walk around by the pilot.
Hardly "sabotage" - even if the pilot had missed seeing it "disconnected", as soon as the system was pressurised during initial pre-flight preparation, it would have shown up then ie. "Hyd Sys A Low Press"
This sounds more like an accidental oversight eg. the aircraft hydraulic system being disconnected to allow work to be done on it, or one of the systems to which it supplies pressure, and forgetting to re-connect it. Poor workmanship.
However the "Drama Queens" have now added "sabotage" to spice it up.