Let me give my reasoning:
In the pre-cap they showed Samar asking Nishaif you are here who is there. This is only to fool us in the weekend and what will follow is he will only remove the gunghat and tell see it is Shivangi.
Iam sure that since he is the hero he only has to take revenge on Nisha like Tit for tat. Afterlistening to Dadi about Mahen not being found he must have got a doubt. Even in previous episode he says who will try to kill naukrani and was watching Nisha. Iam sure he is for sure that somebody must be behind killing Shivangi since he wonly saved her and knew for sure if he was not there she would die.
So he hears her talk on mobile to Anupam and confirms and maybe he will go hospital and get teh truth from Shivangi and plan the whole thing
Maybe in the same way as Nisha did he will take Tannu's help and give her pills and bring Shivangi as bride
He might tell Shivangi that this marriage is not real and choice is yours as once I prove U R Gauri I will take U to Phansi
Our Gauri's priority is family and take revenge on Samar. So she will agree
So thats my story friends.
How did U like it and do you think this will be true?