Need guidance to investigate a potential land grabbing

Hello, my grandfather made a lot of money in his prime and invested in lands. He bought lands in his home town (Kankavli) while working in different state. He had blind trust in his brother and never shared any information with my father. Me and my grandfather had the sweetest bond, but unfortunately, he passed away before I grew mature. Few years back, I remember him returning from kankavli in a devasted situation where he had an argument with his brother and was kicked out of his own house there. After which his health started degrading, and before he could do anything, he was no more. Now his brother is very evil and has taken everything my grandfather earned. Many people (trusted ones) tell me my grandfather bought a lot of land. But when I try to find records on Mahabhulekh, there are no records to be found for my grandfather, his brother or his brother's son. I have more than satisfactory proof that there is a lot of land stolen from us, but unsure how to investigate about it. I request this community to suggest me some ways, or any tricks people use to cover such shady records. I might visit there in the coming few months myself, need a plan for that.