Threatening to give false complaint and witness

Our apartment society is not registered. Some of coowners are jealous of one coowner. They kept a house keeper who lives with his wife in the basement. It is a 12flat apartment. He is not maintaining visitors log and doing personal work of 3 or 4 flat owners. If u ll ask him anything hr is aarogantly replying . his daughter and her family comes and stay with them for 10 15 days. Last night when I came his daughter in law was there. When I asked housekeeper male why you are not maintaining visitors log. While talking her daughter in law came in picture and argued. I asked who are you. Then after casual argument she went upstairs and called 6 to 7 flat owners. They all came and called my father (senior citizen) and 4flat owners directly telling that she will go and lodge a police complaint that your son misbehaved her and they will falsely say that they were the witness. I have recorded all the conversation with her daughter in law. I fear that as he is staying with her wife can give any false case . the flat owners are saying that as he is a house keeper his daughter daughter in law can come . what can I do to prevent such action. Can I do anything legal. I am 1st year law student. I have the video footage of about false witness. Pls advice me.thank you all in advance for your valuable suggestions.