Jan: Surely there should be a safeguarding officer.
There's no official position of the sort, though the expected action would be for a concerned person to speak with an elder and express any concerns, which would then (presumably) be investigated by the body of elders. I don't think there is much in the way of guidelines. Elders would be expected to talk to this person privately and provide spiritual guidance if they considered it necessary.
Ideally, they would not tell the person who expressed concern, but that's not always guaranteed. I have heard too many stories of elders who would become annoyed when anyone 'bothered' them with issues like this. So they would make it a point to identify the person who brought up the issue, thus creating exactly the sort of problems that they were supposed to prevent.
JW elders are handed a Bible and little else, and expected to deal with a wide range of issues, some of which they are clearly not prepared to deal with.