Complex sentence: Nerissa appears and, freed of her ribbon, reveals she and five other women overheard the Crooked Man order the murders; their testimonies are considered sufficient to believe what Bigby did was right.
Split into simpler sentences: Nerissa appears and, freed of her ribbon, reveals she and five other women overheard the Crooked Man order the murders. Their testimonies are considered sufficient to believe what Bigby did was right.