Just because there are no mandatory reporting laws in England, Wales and Scotland (Northern Ireland does) does not mean that the UK government is silent on the subject.
On the contrary there are recommended best practice guidelines - "What to do if you're worried a child is being abused"
One of the first directions is:
10.2 Remember that an allegation of child abuse or neglect may lead to a criminal investigation, so don’t do anything that may jeopardise a police investigation, such as asking a child leading questions or attempting to investigate the allegations of abuse.
Perhaps Prime (or anyone else) can explain how the Watchtower Society child protection policy complies with this basic initial instruction?
The victim in this case was not a child. This is par for the course when a victim tells something to an elder. Victims come forward as adults about abuse that occurred years ago.
To be applicable, the instruction would read;
"What to do if an adult comes to you about abuse that occurred years ago"
No where in the guidelines does it bring such circumstances into question.
"There is no mandatory reporting law in the UK as there is in some other countries: the relevant statutory guidance allows heads to exercise a degree of discretion about what to report."
There is reason to exercise a degree of discretion when it's adults telling you things. It's unlikely that a child would bring anything to an elder, but even if it is not a child, but a minor who is sixteen for example, the elders are instructed not to pursue the matter in anyway before contacting a branch office.