How do you say 彼女は上司にあんな口答えをすべきではない。あんな馬鹿な失敗をして、彼女が悪いのだ。彼女の失敗のせいで我社のとても大切な顧客を失ったのだから。 in English?

She shouldn't have given her boss such back talk, as she herself is to blame for such a silly mistake, which caused us to lose one of our most important clients.