Arsey remarks? Welcome to Salon Geek!
Clearly that is not Cara's actual colour in the photo, but that's not an issue!
Hopefully the highlights are closer to a level 10 than a 9. For the violet tone at the top I would dilute a 1/8 dialight 4.20 (violet) + 1/8 5.66 (red) with a tube of clear. As it develops I'd run it over them ends for a much shorter time, leaving the blue to neutralise the warmth and the remaining red to create a pinkish cast. You can adjust this mixture to your needs. If you want a cooler end result remove the 5,66 and use the red tone from the 4,20 for the pink tone, otherwise the red will look more peach-ish.