Although he also sought support from Yoshimura MIURA, who was Masamura's eboshi-oya (a person who puts an eboshi (formal headwear for court nobles) on a young man's head on his genpuku (attainment of manhood) ceremony), the plot failed in their attempt, and he was exiled to Shinano Province (Incident of the Iga clan).
政村の烏帽子親である三浦義村にも支援を求めたが、計画は未遂に終わり、信濃国に流された（伊賀氏の変）。