After what an insider described as a “messy” dress rehearsal that included several cracked high notes (due to allergies? or nerves?), Olga Borodina may or may not be singing the prima of Cenerentola at the Met tomorrow night. On dit that Joyce di Donato has been rushed through the staging in preparation for a last-minute jump in. (Maybe we should start calling Borodina “Milena Skittish?”)