"...We mustn't bring reproach onto Jehovah organization..."
My elder Dad used to use this argument, but eventually, I realized that that what he personally meant was "we mustn't give our enemies any ammunition to use against us". I couldn't really blame him for feeling that way, considering how he'd been burned by "worldly" people he'd once trusted.
I'll never forget the look on his face when I suggested that that if and when the abuse was eventually exposed, the evidence of coverup couldn't help but bring far worse "reproach", whereas prompt cooperation and proactive reporting would actually garner the respect of public and secular authorities.
Most loyalists can't think that far ahead, though. It certainly hadn't occurred to him, but to his credit, he acknowledged the sense of what I said.
Of course, the real reason this policy has been in place for so long is that the WT leadership knows if the authorities are informed and they start digging, they'll find further evidence of more abuse...
...which, in turn, becomes exposed, and part of the public record...
...which, in turn, becomes harder and harder to dismiss in the eyes of the rank-and-file...
...which, in turn, too deeply undermines the Org's claims of "God's Exclusive Earthly Organization".
And from their POV, that simply cannot be permitted.
The Org's entire raison d'etre hangs on it.