Question: Could the ground maintainance engineers have touched a wire (by accident) that connects to the Reversers when 'Quickly' cutting off the fault??
Answer: Almost certainly not. That's not the way airplanes or mechanics work.
I wish I could be that certain or positive - those of us with longer memories could tell of non-return fuel valves having their nibs deliberately ground off to facilitate their fitting the wrong way round - resulting in a Vanguard ( Aer Lingus ? ) crash. Bad airframe repairs leading to catastrophic failures too. Just because the aeroplane industry is well regulated and inspected does not remove the "that'll do" attitude in everyone.
I'm also quite surprised by the number of self professed experts who post here who are prepared to state catagorically that this or that cannot possible happen only to be completely refuted by actual facts later on.
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