The second-place finish earned the Canadian duo a spot in the Grand Pix Final.
Gilles and Poirier concluded the event with a total score of 157.58.
The Canadians also finished second at Skate Canada.
French duo Gabriella Papadakis and Guillaume Cizeron produced an elegant performance to Wolfgang Amadeus Mozart's Concerto No. 23 to win the completion with a 166.66 total.
American Madison Hubbell and Zachary Donohue (152.11) were third.
Canadians Alexandra Paul and Mitchell Islam (138.99) finished sixth.
Rodionova wins ladies' crown
Two-time junior world champion Elena Radionova of Russia landed all her jumps in the free skate to win the Trophee Bompard on Saturday and qualify for the Grand Prix Final.
Radionova skated to Sergei Rachmaninov's music to score 136.64 points in the free for a 203.92 total. The Skate America winner perfectly executed a long program that included seven triple jumps and three combinations.
Her compatriot Julia Lipnitskaia was second with 185.18 points to also secure a spot at the GP Final. The world championships silver medalist only trailed Radionova by 0.49 point after Friday's short program, but she hurt her chances of winning by falling on a triple flip attempt and underrotating her final combo.
Defending champion Ashley Wagner took third with a 177.74 total. The American skater will have to wait until next week's NHK Trophy in Osaka to see whether she qualifies for the GP Final.
Russia's Elizaveta Tuktamysheva and Anna Pogorilaya have already booked their spots for the GP Final with top-two finishes at other events. Olympic champion Adelina Sotnikova skipped the GP Series because of an ankle injury.
Canada's Veronika Mallet finished 10th with a total score of 139.64.
In pairs, Ksenia Stolbova and Fedor Klimov of Russia tallied 209.81 points to win the gold medal to the "Notre Dame de Paris" musical. The Olympic silver medalists were 9.13 points clear of China's Sui Wenjing and Han Cong, the runners-up at Skate Canada. Both pairs qualified for the GP Final.
Canadiens Kirsten Moore-Towers and Michael Marinaro were seventh with a score of159.13.