Chaudhary played it smart.

She always had plans to give up Shreya's secret.

She never for a moment thought she wouldn't.

She's exactly the revenge type. I mean she wanted to be ruru's( girl on whom yogesh cheated with chaudhary) karma hence she enabled cheating. So that tells a lot abt her revengeful nature.

But she also wanted her secret to be safe. Ofc.

So, she waited for the last turn.

Even during the second last buzzer when ram asked if she's gonna do it, she said abhi socha ni hai last ko dekhte hai.

She was so scared that shilpa would not stick to her words or shreya could manipulate shilpa, so she waited for the last turn.

Fir last ko ye bhi dikhane ka koshish Kiya ki I'm not doing this for revenge, I am a nice person but I'm doing it cz you tried to eliminate me and yogesh. Like girl, make it make sense.

But honestly, the prison cell really changed her. She has mellowed down a bit and isn't as haughty as before.