New Zealand is expected to earn a single elite women's spot for London when quotas are finalised by the UCI.
Experience and patience proved the key at La Bresse with legendary Norwegian Dahle claimed her first World Cup victory in four years.
Double Olympic gold medallist Julien Absalon, who lives nearby, took the men's honours.
Dahle, the 39-year-old Athens Olympic gold medallist and four-time world champion, has had a break from the sport after becoming a mother. She was back in fourth until the leader, Canada's Katherine Pendrell, crashed on the demanding downhill with series leader Julie Bresset, of France, falling while trying to avoid her.
Czech Katerina Nash took control from Dahle before she fell twice on the final descent to allow the Norwegian through for the victory.
"It's unbelievable," said Dahle.
"I am first of all a mum. So I can't believe it. I was focusing on not going over my limit.
"I thought she might be over her limit and she was.
"I did a very good race on this course which was tough up and tough down."
The shining light for New Zealand at La Bresse was another outstanding ride by Samara Sheppard who was third in the under-23 race on Saturday following her fourth placing in the last round as she moved to eighth on the overall classification after four rounds.
The cross country battle moves to North American for rounds in Canada and USA in late June, while the downhillers are back in action with the World Cup at Val de Sole in Italy in two weeks.