The highlands of PNG were only opened to civilization in 1947, when an Australian bush pilot noticed villages. The climate is perfect: near the equator at 8,000 feet. The natives have been there for a few thousand years, having emigrated from southeast Asia.
The various tribes constantly fought, with continual bloodshed. Supposedly as a result of that, a tradition developed that the womenfolk would smother to death male babies to reduce the violent male plague. When a first census was taken, there were far more females than males. Surprise, surprise.
With this background, I am skeptical of the woman's story. This may be ancient tradition rearing its head.
I think your dates are off. Margaret Mead's book about the isolated tribes of PNG was years earlier than 1947. "Sex and Temperament in Three Primitive Societies (1935)"
"Growing Up in New Guinea" is a 1930 publication by Margaret Mead. The book is about her encounters with the indigenous people of the Manus Province of Papua New Guinea before they had been changed by missionaries and other western influences. She compares their views on family, marriage, sex, child rearing, and religious beliefs to those of westerners.