The argument about parents is one I am starting to hear from dubs to deflect responsibility away from the organisation. I am sure that in some cases abuse may not had happened or been less extensive had parents been less trusting with members of the congregation. However this does not mean you simply blame the parents.
Peadophiles become masters of subterfuge and manipulation. There is a reason the preparation of a child for abuse is called "grooming". The process is not limited to the child, it extends to the family and friends to enable abuse to occur. Often abusers are within the close or extended family, even parents.
I am sure there is not one parent of an abused child that does not look back and wish they had done things differently, regrets actions they made or decisions they took that in some way enabled an abuser to harm their child but to start blaming parents above the abuser is simply unfair and only deflects away from the real problem.
The WTS is allowing an over simplification of the cause of the problem to become a stock response. They are happy to let R&F Witnesses blame parents and become all indignant that parents or the victim have relied on the elders and not gone straight to the authorities. This kind of apologist nonsense has no place here.