Today the owner of the Good2go dairy and video hire on Auckland's North Shore, Raj Patel, confirmed there was pornography on the DVD sold in the bin - but he maintained he had done everything he could for the customer.
"I have apologised to her and straight away - within five seconds - the DVD was broken and put into the bin."
He said there was no way of finding out how the DVD got dubbed as any number of people had the opportunity to over-ride it.
He accused Williams of bringing his business into disrepute and threatened legal action for approaching the media.
"If she is trying to say our business is at fault we are not at fault.
"We will take action against her for discriminating us."
However, Williams said she was not satisfied the store had done enough.
She claimed the store could have vetted the rental to intercept the work of a "sick" person recording pornography over a children's film.
"Someone has got out a kid's DVD and put their own thing on them.
"It's revolting. It's not okay."
She said the episode had scarred her little boy who only wanted to watch elves and Santa.
"At the time I told him someone had put the wrong DVD in the case and that I was sorry he had seen it.
"Now whenever I get him a DVD he asks me, 'mum, is this going to be another naked DVD'?"
She feared other young children may inadvertently have seen the adult-only content.
Williams said the shop owner had said there was nothing he could do about it.
From now on Williams said she would vigilantly check every DVD before her son watched them.
Patel said this was the first time he had inadvertently sold a porn DVD.
"In 10,000 DVDs I have never had a case like this since taking over the business 6 years ago."
He said another customer had likely over-ridden the DVD, which dated back at least 10 years.
Patel said no video rental store played returned videos, but instead checked for scratches and other damage.
He said his business had taken a moral stand against supplying pornographic movies by choosing not to sell them.