I think many may feel confused as to what the so called 'RAAZ' was all about.. and how will it help SuKK get back together. Initially, I too was confused.. but now things seem to be very clear.. for me atleast. Am posting my understanding of the whole situation..
The RAAZ was basically a pact between SuKK..which, unfortunately took its toll on them now..all due to misunderstandings created under unavoidable circumstances. 25 years ago, Su professed his love to KK..which she, initially, rejected..then accepted. Su promised KK he would never leave her..and if she feels betrayed by him, she can let go of him..leave him.
Back to the present.. all along, despite Su lieing to KK and all proof pointing towards Su-Nivi, Su thought/hoped that KK would not let go of her trust off him.. Su hoped KK will trust that there is something which he is unable to tell..but he won't betray her. KK letting go of Su (which comes from a decision they took so long ago) has made Su realise that KK believed Su betrayed her and that he is having an affair with Nivi.
Now Su has realised he has to do something quick to reaffirm KK's trust in him.. Su has realised its time for some action now, as KK has completely lost faith in Su.. This is totally Su's "agnipariksha".. He has not done anything wrong..he loves his wife.. yet he has to prove it now.
Its very crystal clear for me.. dunno how much it is for you'll. 😊