My disappointment in NM just got bigger

I thought i was able to do this cup because i only need 3 more stage 6. But i got 2 duplicates. 1 from the golden cup and 1 from my 7 crates. Kind of sad because i was looking forward to this cup.

Why is there still no way to prevent stage 6 duplicates for these events. Hopefully i can get one of the parts from my daily crates because stuck at 8.6 seconds now