Cancellation of sale deed

Dear All, I need your guidance on illegal registry of land taken place in 2006/07 in West Bengal. My mother was a partner in one company ABC and this company were operated by her brothers in law and it was going great.In 2005,their brothers in law started cheating her and shifted all the business to another company which was in their personal name.Now under this company ABC there was a land purchased by the company and advance given to seller in the name of all partners of equal share of 20% and the same was notarized.In 2006/07,their brothers in law illegally registered the land in their name by bribing the seller. Later in 2012/13,when it came to our knowledge we had filed arbitration case on the company and brothers in law and accepted the fact they had illegally registered the land in their personal name and this case is still going on in Calcutta high court. Now we want to file criminal case and cancellation of sale deeds to get our share and compensation for the damages other than arbitration. Please guide us on this matter and advise what are the corrective actions we can take other than arbitration act. Thanks Regards Mohammad