Complex sentence: She sends them to the school principal, who threatens to expel the culprits, who were Nikki, Tiffany, and Ezra (Joey Nappo), another tormentor, if they deny that they cyber-bullied Vanessa, they would be expelled from the school and not graduate.
Split into simpler sentences: She sends them to the school principal, who threatens to expel the culprits, who were Nikki, Tiffany, and Ezra (Joey Nappo), another tormentor. If they deny that they cyber-bullied Vanessa, they would be expelled from the school and not graduate.