Mo Martin, a former Women's British Open victor, was two shots back on 10 under.
For her sixth and the biggest victory of her career, Stanford will take home $577,500 in prize money. In 2009, her mother was diagnosed with invasive lobular carcinoma breast cancer but would fight her way through multiple surgeries and chemotherapy to become symptom free for nearly eight years.
Wu had an eagle putt on the final hole at The Dutch in Spijk that narrowly missed, leaving him a tap-in bidie for a 4-under 67.
Seven-time major victor Inbee Park and Women's British Open champion Georgia Hall are in the running at nine under along with Angela Stanford.
The 26-year-old signed for a 74 to slip into a four-way tie for second spot alongside fellow Americans Austin Ernst and Mo Martin and Sei Young Kim of South Korea.
"It's disappointing to finish like that", said Olson, whose previous best finish in an LPGA tournament was a tie for seventh in 2014 Lotte Championship in Hawaii.More news: Is Ronan Frank's Child - Woody Allen Isn't Sure
"I really hope that this is what I'll be able to do with my life in a few years after college, " said Heck, a Memphis, Tenn., native who is to attend Stanford University.
"I would say actually I was driving the ball better during ANA, but I'm putting a lot better this week", she said.
"It's something new and it's exciting [to lead]", said the 23-year-old Torres, who is ranked No. 184.
Olson committed to not looking at leaderboards throughout the day, and it wasn't until she was sizing up her options from the rough on the 18 that she asked brother Nathan, her caddie, where she stood.
Scott McCarron shot a 9-under 63 on Saturday at Warwick Hills for a share of The Ally Challenge lead with Tom Lehman and Jeff Maggert. The victor two weeks ago in Canada, McCarron dropped four strokes on the final two holes on the front nine, making a bogey on the par-3 eighth and a triple bogey on the par-4 ninth. Tom Lehman bogeyed the 18th for a 70 to drop into a tie for third with Mark O'Meara (69) at 13 under. First-round leader Brandt Jobe had a 71 to drop into a tie for eighth with David McKenzie (69) at 8 under.
Hyang Lee was one stroke worse after shooting a 73. He had six birdies and a bogey on his second nine, birdieing the last three and four of the final five.
At 40, Stanford is still waiting for that elusive major, but she's giving herself a chance at the Evian Championship.