Chuti Nanaji may be a grey character, but he didnt change the WILL.
Before Nanaji died he lamented about his brother away from him and he actually begged Anuj to look for him and bring him back to him. So including him in the mansion makes alot of sense because Nanaji knows the family will throw him out if he doesnt have the right in the house. But he didnt include him in the bussiness because he doesn't trust him enough.
Nanaji gave everything to Pankhu because he knows she has a great heart. She will make sure the family is kept together.
He made sure Harish is the final decision maker because he know Pankhuri is very weak and would give everything to someone out of frustration. He know Harish is a very strong guy that think not only with his heart, but with his head.
He didnt give the rest because some think with only their heads like Avantika, Rubal, Latika, Mami. and others think with only their hearts like Aditya, Kaira, and Preity
while he is not sure of Anuj at this point.
He knows this will be a long battle but he knows Pankhuri and Harish will win it. He know Pankhuri will respect Avantika, Masi and Aditya enough to guide her every steps. and he know his brother's wife is bad, but He wants pankhuri to bring the brother's family together with them.
I may not have strong logic behind the will be Something tells me its nanaji's will.