While Malvolio and Sebastian were in a confrontation, Sabrina was persuading Isadora.

"Let me go up. I'll go and persuade my husband. I promise to let my husband show mercy to you and your brother and never take your lives."

Sabrina was indeed thinking to do so. She wanted Sebastian to let the two siblings, Malvolio and Isadora, go. After all, Malvolio had always been very polite to her in the past few days on the island. He also did not torture Holden much either. Not to mention that Isadora