In a statement released in July after the Observer article, which included allegations from Mrs Hemmings, Ms Winn acknowledged making “mistakes” earlier in her career.
She said it had been a pressured time, and although she was questioned by police, she was not charged.
“Any mistakes I made during the years in that office, I deeply regret, and I am truly sorry,” she said.
Ms Winn said the case had been settled between her and her ex-employer on a “non-admissions basis”, because she “did not have the evidence required to support what happened”.
She said: “Mr Hemmings was as keen to reach a private resolution as I was.”
BBC Wales put Ms Winn’s statement to Mrs Hemmings.
She responded: “I think she’s just trying to put the best spin on the question.
“The mistake was that we ever employed her, and the biggest mistake my husband made, because obviously I’d recommended her in a way, was that he trusted her.”
The Salt Path has sold more than two million copies since its publication, and Ms Winn has written two sequels, The Wild Silence and Landlines, which also focus on themes of nature, wild camping, homelessness and walking.
Mrs Hemmings said she had not read The Salt Path because she did not feel it would reflect her view on why the couple did the walk.
She added: “I’d have stamped on the book I think. Just to gloss over why they ran out of money to me was shocking.”
Her daughter Debbie said: “I don’t wish ill of them. I just wish that they would tell the truth, and the truth needs to be told.”