I beat Argenta earlier today with my Level 70 Flareon -- she had a Yanmega that used Endure twice in a row but failed on the second attempt after a Petaya Berry boosted its Special Attack and Speed Boost activated. Just two Flamethrowers... and I had a Silver Print!
I've watched the video a couple times and LOLed...
In my 50-win streak, I battled against Normal, Fire, Electric, Grass, Ice, Flying, Poison, Bug, Dark and Steel types. The funny thing is... whenever I chose to battle against a Poison-type... all of them were either of the Grass/Poison or Bug/Poison type!
Update: 60 wins! I might be able to get Flareon to 70 or 80 depending on the opponents' Pokemon. She's at Level 71 now.