lodged a false case of threatening

My cousin brother who is 8 years younger to me lodged a threatening case against me. My eldest (own) sister entered into a verbal agreement to reconstruct a demolished residential building of my mother's younger cousin sister. During the course of construction, my sister observed that my aunt's family had forged her signatures of paying excess by Rs. 4 lacs. Also that the building doesn't have necessary approvals by Municipality and Town Planning Departments. By the time she realized, the construction was half done ( G+1 of G+4) and the major construction materials such as steel and cement were purchased for all the four levels. My sister brought the issues to the notice of my aunt's family and stopped the work seeking termination of verbal agreement and to settle the accounts and pay the amounts which my sister had already invested in procuring the building materials as she felt entitled to. My aunt served my sister a lawyer notice that stated there is huge dump of unwanted steel lying in the construction steel. Following which, my sister along with her husband went to the construction site around 9 pm to remove the steel from the site.( because the road is very narrow in front of the site and nothing as such can happen during day time due to heavy vehicular traffic as the construction site is just adjacent to the main road). My aunt's family objected her from removing the steel from the site and lodged a theft case against my sister. My sister (an engineer by profession and a mother of 3 children) was astonished to the unexpected move by my aunt's family. My sister was made to sit in the Police Station from 10 pm to 3 am. My mother called me at around 1.30 am (almost midnight) and informed me about the incident. On that day, it was my 33rd day of my 36 day contractual vacation as I work in Saudi Arabia. I along with my wife went to the police station to find out what actually happened. Since the complainant is my younger cousin, and as an eldest cousin I tried to convince him to settle the matter at a family gathering but in vain. To my surprise and dismay, later after 2 days, I received a call from Sub Inspector of Police to make myself present before him. I visited the police station the following two days but could not meet the Inspector as he was not available in his office. Eventually, having tried to meet the inspector for two days in vain, the third day I have travelled to Saudi Arabia as my Visa would expire on fifth day. After 9 days I reported to work, my wife in India received a call from Sub Inspector asking to present me before him. When she explained to him about my reporting back to office, the inspector asked my wife to be present in his office. My wife met the Inspector in the Police Station and was handed over the complaint copy with crime number and year. She was asked to represent me on my behalf. The complaint reads as that I threatened my younger cousin in front of the construction site during that night when the Inspector retained my sister in the police station where as I never spoke to him directly or indirectly. Neither did I call my cousin in the past 10 years nor did I meet him any time in the recent past even until the construction dispute came up. My wife recently joined in a B Ed college as a Lecturer and would not be able to frequently attend police station or court due to nature of her job and also that she would not get leave of absence. My wife is staying in India with my two daughters studying in Primary and kindergarten sections. I think that my aunt's family is only trying to put me and my family to trouble to cover up their insecurity feeling. Kindly suggest me as to how can I should respond to the Inspector's call. Can I file a defamation case against my brother for lodging a false complaint against me saying I threatened him in front of one of his relative. Kindly advise. Sincerely