fraud customer at the bank -need advise

Dear sir, I want to ask a question for a incident happened with me in MAY I am Banker working with private bank and living in Delhi On my part I have to handle the cash in the branch , On 2 may I had made a mistake and gave over payment to a customer from his savings account which is RS 2,71,154 instead of giving Rs 27,154. I realised my mistakes just 20 minutes later while tallying the cash after confirming it from the CCTV footage I sent peoples from my bank to get the money back. But the customer refused to give the cash back. He is accepting that he has the excess cash but due to some dispute with the bank he is denying to give the cash back. So we lodged a complaint to police station. But no serious action was taken by there end, On the other hand customer is also threatening me by saying that he will file FIR against me and because I tried to meet his mother regarding this matter and he also abused me. We have CCTV clip ( recording of her sister admitted that they have excess cash of that case) and witnesses as well, police is saying to go to the court ,so we marked a mail to our bank's legal team but they are not taking it serious .Now i want legal advice what i have to do should i go individual for court case against him? kindly advise Regards Neha Pandey