Ancestral Property Dispute

My lawyer grandfather won a case in 1960's and got 6 acres of land as fees from his client. He put this land on his father's (my great grandpa) name, which eventually went to all his 5 brothers at a share of 1.2 acres each. My grandpa sold his share of 1.2acres in 70s. The remaining land was left barren and little bit occupied illegally. My father in 1989 bought the 3.6 acres from his 3 uncles (2nd, 4th & 5th but 3rd uncle didn't want to sell) at an agreed price. He got signatures from his uncles on a revenue stamp paper but not registered the land. Most of his cousins dint sign those documents. He worked on the land and got it to cultivated form. He has been paying taxes since 1990 and curently online titles are on his name. But there are no original land titles from first seller. Besides the 3.6 acres, he also bought 2 acres of adjacent land in the same survey no.s. One acre on his name and 1 acre on my mother's name. So totally we had 5.6 acres of land under the same survey no.s. In 2012, due to need of money, we sold this 5.6 acre land. 20 laks was given as advance and 3 months time to pay the remaining money and get it registered. My father also gave "Right of Possesion" to the buyer during the agreement time. Meanwhile before registration, my father's cousins (children of my father's 4 uncles) got together and put legal cases on my dad in 2012. The cases have been ongoing for last 10 years. The buyer is neither paying the remaining money and getting it registered nor paying us the lease money for cultivation. He is using the land for cultivation. We have tried to get it settled out of court many times but during all these years nothing worked out neither from buyer side nor from my fathers cousins. Now our lawyer brought a person who does land settlements. He wants to buy this land (ofcourse at a lower price), pay us the money and get the land registered confidentially. He says he will take the onus of settling the issue with the current buyer as well as my father's cousins and we will not have any issue from them in future. But we are not fully clear about this process how it can happen. Our questions in this regard are: 1. Is this way safer to get the land issue resolved ? 2. Can the current buyer put a cheating (criminal) case on my father? As there is agreement for 20 lakhs advance paid and also right of possession document. During last time talks, the current buyer agreed to pay the lease money for all these years for cultivating and get the land registered but there is no written document for this. 3. Any other hassles if we go through this way of settlement with another buyer? My lawyer says, if we have to actually proceed legally then we have put a case against the current buyer that he is not getting it registered nor releasing the land and this process will again take years.