I also think that Shashank is a guest appearance,but he will definately marry Gauri.But,something drastic will happen in Gauri's life(like Shashank will die)and after that Shiv will feel sad for Gauri 😭 .As a result he will start caring for her 😊 ,then love ❤️ will happen,and he will ask her hand in marriage 🤗.
Gauri will transform Shiv into a changed man 👏 .