Silver hair gone wrong

Hi guys. I hope I'm posting this in the right place. I couldn't find a post similar to my problem, so I decided to make a new topic. Please forgive me if I made any mistakes, I'm still new to this.
Now let me introduce you to my ultimate problem.. I had a brassy blonde hair. I stripped my hair form green colour using Color Zap, so after that some strands were darker than others. Instead of bleaching the hair again, I just used Wella T18 toner, to remove brassy tones. The parts that were dark yellow, turned lighter, but still apparently not enough to be covered by silver hair dye. I used Pravana Silver to dye my hair and now the lighter parts turned silver, the yellow parts are light blonde. What can I do to fix those blonde parts? Do I have to use wella toner again? Or apply more Silver dye? I really don't want to bleach my hair again.
I'll be super thankful for any advice.