Scheme of Amalgamation of Tata steel and Indian Steel &Wire Products.l Recieved DD Today.

I got a DD dated 11august 2024 from my cousin family ,It's in my dadus name he had 1300 share of India and steel and wires products ltd. After NCLT Process tata is buying back at 426/ per share. My dadu,dadi and Dad is no more and we want this to get transferred in our name . Dad has 2 sisters. 1.Whom should I contact for legally transferring in my mom name? 2.How can I know if other shares our in his name,because he expired in 1996 and lot of them are in physical form. Thankyou for helping me out.