As a not, never have been a JW, but a retired professional who dealt with too much child abuse, can I please post this plea?
Do not ever, ever, allow anyone (apart from parents/carers of course) anywhere near a child abuse victim unless and until the professionals have done their jobs and finished with their interviews. The parents/carers should share no details with anyone else - especially not the alleged or putative abuser or anyone connected with them.
The professionals work under very strict guidelines and rules to ensure that the evidence of the victim is not 'tainted' - i.e. can't be excluded by a court.
There is nothing more distressing than a victim who has gone through the pain and horror of all this only to find that because others have got involved (and that would include 'elders' of a mind control cult) their evidence, which they have gone through so much pain to give, is discounted.
I don't mean to sound preachy, but this is something I feel very strongly about.
ALL and ANY suspicions of abuse should be reported immediately. It is a principle of the law in these matters (in the UK at least) that 'early complaint' may be a corroborative factor.