cofty - "...Is it the scale of the problem that they need to keep secret or are there particular names that need to be protected...?"
Probably both...
...but I suspect it's far more the former than the latter.
Remember, a brother found guilty by a JC "may" still be eligible for "privileges" after a certain amount of time if the offense isn't widely known.
And considering how fewer and fewer qualified guys are "reaching out" (to the point where Top-Shelf Tony has essentially threatened them with male spinsterhood if they don't), the bOrg has gotta be scraping the bottom of the barrel for congregation administrators by now...
...to the point where they have no choice to appoint more and more ("repentent") abusers, simply because there's too few left.
The more the WTS is required to report, the harder it will be to keep the rank-and-file in the dark (i.e. keeping the sheer scope of the problem on the DL), and the pool of candidates dries right the fuck up.
And if the rank-and-file - particularly parents - put together that their only remaining MSs and elders are pedophiles (or are protecting pedophiles), well...
...good luck functioning at the grassroots level (let alone convincing them that the WTS is "God's Earthly Organization") when that happens.