Yamazaki Fans why didn't shingen come back beat all the fist gang no diff and jumped gapryong with all the yamazaki to regain south korea.Is he stupid or are his advisors stupid who couldn't think of such a plan

shingen can easily 1 vs all and extreme diff gap even after 1 vs all so he should have just jumped gap with his other fodders.Are Yakuzas this dumb that they cannot make such a plan.Why lose all that money and influence over such a small thing