She was smarter than Chloe, and quickly thought of Casiano. Mrs. Harris had told her that the despicable Alla was dead, and Casiano had even attempted suicide by slitting his wrist at her grave. Coincidentally, just before Alla's death, she and Chloe had attacked her in the restroom, and Casiano was there too! He even spoke up for Alla when Chloe wanted to kill her on the spot.
Had it not been for Chloe's insistence on telling Mrs. Harris, Casiano probably wouldn't have slapped Alla. It was that slap that dispelled her doubts! Who would have thought that he was afraid the Harris family would find out about Alla, so he deliberately put on a show in front of them! Casiano had been involved with that despicable woman for five years, yet he could act as if nothing had happened. He was really good at hiding!