If they copy YRKKH kairav custody tarck then in there they show naira breakdown in courtroom and FB she face so many problem during pregnancy. sai ka breakdown and blame to V and P is very necessary to connect story after that V realization and P breakdown.
I dont know how they revel Vinu identity maybe they show he is real vinu or not? because they know about real vinu only major disease which cause surrogacy or some person who is with sai during bus accident and they give to vinu in orphanage and they know his name is vinayak, and s met them and they revel to vinu.