The answer is still yes... The very fact that author preferred the Norwegian version over the Swedish one, doesn't make it any less of a Huldra.Now for those saying that she is based on the Huldra, well the answer is no. In the myth, there were stories where the Huldra possessed a cow tail, while in other stories, she had a fox tail and a hollow-covered back.
.P.S.: And they normally depicted with either a tail (be it cow, be it fox, matter does it not) or a hollow back, NEVER with both of them.