Bank delaying auction property registration

Dear sir, on 16.03.2017 I participated in an auction of properties belongs defaulters (group of 3 people took loan to establish industry in 2009 by mortgaging some properties and defaulted for an amount Rs. 12 crores.) of Indian Bank. I'm the highest bidder for an independent AC Sheet roof residential shed for 25 Lakh, on the same day bank AO issued a letter of confirmation. I paid 25% money on the same day (10% already paid as EMD). Bank didn't issue sale confirmation letter and said the defaulter has approached DRT and DRT issued stay. Finally on 11.04.2017, bank issued sale confirmation letter and stated that the remaining 75% money would be paid by 26.04.2017. I arranged the money by withdrawing some of my savings and also by taking personal loan, now bank manager saying that again the borrower approached DRT and expecting a notice from DRT to bank and he will intimate whether to pay or not remaining 75% money. In this scenario 1. Should I believe the bank manager ? 2. should I pay remaining 75% money to bank or not. 2. If doesn't pay how to take back my 25% already paid amount( in sale confirmation letter stated that, If I fail to pay 75% within 15 days, earlier paid 25% amount would be forfeited). 3. If I pay 75% amount, will this transaction completed smoothly or do I face any future court case problems from the defaulter borrower.