Canadian Wilson lit up the event with her enthusiasm and charisma, and was cruelly denied the points for both the team and Silver Saddle leading individual rider awards by Peslier himself in the Classic.
Peslier said: "I'm very happy. It's been a competition everyone could follow until the end. Everything happened in the last race."
Having won two races already, Wilson dropped her stick in the closing stages and her mount Astronereus was beaten just a nose by Peslier and Our Gabrial (8-1), with the Frenchman's more consistent finishing across the board sealing the prizes after neither the Girls nor Europe could land a blow in the concluding Sprint.
Europe ended up with 69 against the Girls on 68, although winning skipper Frankie Dettori was not exactly thrilled by his own role in the win.
"What a captain I am," said the Italian wryly. "I'm different class! Three points and four of my horses lame. Thank goodness for the other two. But in truth we did have the most experienced team. And we just had to beat those girls.
"Olivier has been my good friend for more than 20 years. Just a wonderful natural jockey, cooler than a cucumber when it mattered, as cool as an iceberg.
"Adrie [de Vies] is so talented and as nice a guy as you will meet, and a world-class jockey, even if he isn't so well known here as Olivier.
"But that's the great thing about the Shergar Cup, it gives people a chance to see these top riders. It's great fun for us and I hope it is great fun to watch."
With well over 1000 winners at home, Wilson, 32, is no novice to the game but she undoubtedly embraced it best.
Having drawn a blank from two previous Shergar Cups, she punched the air after helping the Lady Cecil-trained Retirement Plan (7-1) collar an enterprising De Vries on 25-1 shot Buckland in the Stayers.
"It means absolutely everything, I'm elated," she said. "It's not just winning the Shergar Cup for the team, winning a race over here means a lot to me personally.
"Ten years ago when I started riding I never dreamed I'd be here in this position. I'm proud to be here, and proud to be a Canadian."
After her Stayers heroics, Wilson then got the Dandy Nicholls-trained Don't Call Me (5-1) home by a neck in a blanket finish to the Mile.
"I said to the trainer if his horse disappears from the yard and is suddenly on a plane to Canada I've got nothing to do with it," she added.
Nicholls, for his part, was highly impressed, and said: "She'd seen the videos, done her homework and knew exactly what she wanted to do. Fair play to her, she did exactly what she said. This horse is a different beast around Ascot."
Craig Williams has won multiple Group Ones worldwide, but he was another rider to break his Shergar Cup duck in the opening Dash.
The Australian has ridden around Ascot many times and sat prominently on Robert Cowell's 7-2 favourite Goldream, holding on by a head for the Rest of the World.
Williams thanked the sponsors and the hosts, before saying: "It's the third time I've ridden in it and my first winner so I've probably got more points on the board than from my other two times [in total]. I love the concept here and the way the public embrace it - it's one of those events you hope to get the phone call for."
Tom Queally secured a comfortable victory for Great Britain & Ireland in the Challenge aboard Semeen (6-1) for Luca Cumani, but the Sprint race was mired in controversy when winner-by-a-nose Richard Hughes and runner-up Jimmy Fortune were both given two-day bans for excessive use of the whip on their mounts, Highland Acclaim and Golden Steps respectively.