Lost of agreement

Hello, I need some suggestion as I am in the process of selling my current house. My property was purchased by first buyer in the year 2002. He sold his house to second buyer in year 2008. And in year 2013 I became the third buyer. Now the second buyer had lost the first buyers agreement which came into my attention at very late stage. Now I am planning to sell the house but I don't have the original agreement of first buyer, but some how I still managed to get a xerox copy of the lost agreement. I read somewhere that to get a duplicate agreement I ll have to file a FIR report and some newspaper ads. But this was lost by the second buyer and he is no more staying in India. Now my questions are: Will there be any complications on selling my flat without having original first agreement? The new tentative buyer is opting for home loan, will bank ask for first original agreement? On behalf of second buyer, can I still go ahead and create a FIR report without him getting involved as he has permanently left India? Is there any other way of getting my xerox copied version as certified copy? Or any other solution?