Gift settlement

Hi sir in 2008 defendant 1 gave a gift settlement to plaintiff and got registered. Next day defendant 1 cancelled the gift settlement unilateral reason stated was " I expected something but it didn't happen" and made a sale agreement with defendant 2 relative witnessed by defendant 2 and his son. By the end of the month one more gift settlement was executed by defendant 1 to defendant 2 witnessed by defendant 2 relative. Defendant 1 deceased on the same year before that he sent a last memo to plaintiff saying that plaintiff forced to execute the gift settlement signed by defendant 1 and 2 together. This was the case in trail court plaintiff won th case Now the defendant 2 appealed in high court and requesting to add new documents which is a will written on 2003 in that the defendant 1 wrote the property to defendant 2. Further he is requesting the court to enquire my attested witness for gift settlement. Plaintiff didn't call the attested witness for examination in trail court. Still property tax and electricity bill is in defendant 2 name but plaintiff objected and sent a RTI notice register office before filing the case in trail court. As I mentioned before plaintiff name is reflecting in ec. But later and cancelled and moved in defendant 2 name now once again it is in plaintiff name as he won the case. My question is Can I avoid bringing my attested witness to court? As the defendant 2 is rich there might be chance of bribing him? Is my gift settlement still strong?