We know they cannot go back because they are needed to bring ShaNak close.
Khusbhoo wants to use them too, so she is bound to make some excuse to keep them here. But how can she do it, without giving up her status?
Mangal seeing Shaan hug Natasha, and Hetal hearing Khanak mention Natasha's name to Shaan- these scenes are important. Can anyone guess how? I am not able to...