Perhaps this is all Kakisa's doing....

We all note that Saloni doesn't speak back to Kakisa ever.

Perhaps Kakisa is the blackmailer, and told Saloni that she will hurt everyone terribly, if Saloni doesn't do as per her wishes.

Kakisa's main enmity is with Saloni, as it was Saloni, who had helped in exposing Kakisa regarding Chadni's death.