Problem in obtaining death certificate

An aged person passed away in home (natural death). The doctor's death confirmation letter obtained. The burrial has to be done in native village, so the remains were transported through ambulance (private). The advance payment and final payment were done to the driver on Gpay. The family did not know that ambulance receipts is required for obtaining death certificate in city corporation office. The coporation requires doctor certificate, burrial certificate from VAO and ambulance receipt for processing death certificate. When the family approached the ambulance services, they are asking for extra Rs.15,000 money for giving ambulance receipt. The family's only proof is the gpay payment. Given the difficult situation, the family were not aware to record the ambulance number or photos of the ambulance, hence no such proofs are available. How to address this situation? Can the corporation office accept the gpay screenshots as proof for ambulance or can death ceritifcate be obtained without ambulance receipt? What other methods or actions can be taken to resolve this issue?