They don't need to scrap the policy. What they choose to do as far as their internal club rules are concerned is up to them. At a high level, the principle of requiring corroborative evidence is a sound one in terms of the execution of justice.
As jwfacts says, they don't actually have to compromise their interpretation of scripture to accommodate more robust procedures when faced with an allegation of child abuse. They just need to modify the policy and the reality is that they have taken some steps to do this.
The utterly bizarre situation is that instead of publicising the policy changes, promoting and reinforcing a culture where elders support the victim and get help from the authorities - something that would help their cause as far the secular authorities are concerned - they instead choose to reiterate their dogmatic view of scripture.
This is why my fear is that whatever the policy changes there will still be a disproportionate risk of these allegations being handled badly since the organisation from the top down simply seems to be reverting to type. Clueless indeed @jwfacts.