The point about duty to warn the congregation is covered in the court documents:
https://jwleaks.files.wordpress.com/2015/04/04-13-2015-appeals-court-final-decision-a136641.pdf
Check page 12 onwards - there is several pages of legal reasoning.
The punitive damages were based on the duty to warn the congregation. Since the ruling was there was no LEGAL duty to warn the congregation then the punitive damages were removed.
When you real the documentation you can see why this was not upheld and what the broader implications are should this duty have been established as a legal responsibility.
Of course, this does affect the MORAL responsibility to protect the congregation as far as is possible. It does not mean that some policy cannot be formulated that helps protect the congregation as much as possible from the risk of child molestation without exposing the congregation to the broader implications of a duty to protect from the risk of one congregation member committing a crime of any sort against another.
It is bizarre that the WTS is so ready to spout on about when things, such as building projects, have been done to a standard way beyond that required by the law yet on this matter seem only too happy to go only as far as the law requires them to go and not implement the best practice that so many other organisations have adopted.