What is the use of a civil suit if the person could not be traced?
If a person who owes large amounts of money to another person, is absconding, who will help to trace him, if not the State? Private detectives will not be able to investigate without breaking law. If a person borrows money and then vanishes it is like theft or cheating and should come under criminal law.
Earlier issuing a dud cheque by itself was not a criminal offence unless deliberate intention to cheat was proved. But after NIA-138 was introduced issuing a cheque itself became a criminal offence.
What the father's friend did amounted to a criminal offence and a police complaint can be made. Whether the police will act and act with diligence is a big question. But that is so in the case of any other criminal offence too.