if 50 % kurama's shroud wrapped with perfect sussano fails, then
1) Naruto get other half of kurama from Minato
2) 100% Kurama's shroud wrapped in perfect sussano happen
3) 100% Kurama's shroud enhanced with senjuts and curse seal Perfect Sussano happen
4) 100% Kurama BSM Naruto wrapped in curse seal perfect sussano happen.
If all of these fail then only hope is plot no jutsu:
1) bringing Yata mirror and totsuka blade by Sasuke
2) Sage of six paths appearing inside Naruto and give all powers to Naruto or merging with him
3) Naruto getting pseudo ten tails mode
4) Naruto releasing bijuu using names as spell
Thay all I can think of
