Part of it was heir's momma was Mariko's childhood buddy, kept saying Mariko always did things perfectly, was probably moved by Mariko showing some massive balls defying the ban on leaving w/o a permit and going as far as physically fighting off the guards a bit, the old lady telling heir's momma quit playing games, seeing Mariko is the one with the principles and character while she's having sexual relations with whoever currently has the power, but the main thing was probably Mariko's drop the mic dunk on your head poetry line.