Deborah Howell was likely taking photo at time of death
Based on pictures of the scene published by the New Zealand press, the landscape seemed relatively pastoral, which was at odds with the reports of a car accident while she was on foot.
But the last paragraph of this Pioneer Press story would seem to explain it: Howell had likely gotten out of the car to take a photo.
Nick Coleman said that from what he could gather, Howell likely died while trying to take a photo. He said that she'd been sending photos to family during her trip and that she probably made the driver stop so she could get out and snap a shot. "She died doing the journalistic duty. ... That would be typical of her."