Cassie weaved her way between people as she approached Chloe. She glanced around to make sure they are not overheard before asking Chloe: "Do you know what Samantha is up to?"
Cassie saw that Chloe and Samantha parted ways and that Samantha went to talk to Victor and Samuel. Considering that she heard Victor's and Samuel's negative remarks directed at Corey, and knowing Samantha, she assumed that Victor, Samuel, and Samantha are going to target the couple.
It's not that Cassie planned to intervene, but she wanted to know what was going on.
Chloe pressed her lips into a line and observed Cassie while wondering how much she should say. Cassie was following Samantha for years, so it was natural that Cassie and Chloe are familiar with each other. Also, Chloe was not sure if Cassie has loose lips due to her lack of intelligence, or she spreads gossip intentionally, but Chloe was aware that Cassie is not someone who should be trusted.