You have stated that this incidence is reportedly happened around 5 years back, what were you doing all these years.
Your father died due to the chronic ailments and the complications developed due to it.
Verbal quarreling and shouting at high pitch of voice during quarrels are common, this cannot be considered as intimidation.
Your father was a heart patient so his complain about his chest paid after two days of the incidence cannot be related to this incidence, even otherwise the remedy was that he could have lodged a complaint with the police for criminal intimidation immediately after the incidence. The criminal intimidation as per law means
Whoever threatens another with any injury to his person, reputation or property, or to the person or reputation of anyone in whom that person is interested, with intent to cause alarm to that person, or to cause that person to do any act which he is not legally bound to do, or to omit to do any act which that person is legally entitled to do, as the means of avoiding the execution of such threat, commits criminal intimidation.
Further your father breathed his last only after two months of his last health complaint,so there is no reason to book that person that too at this belated stage.
Your problem is about the person who is walking free which can be seen from your contents ""Since i am in trauma after this as person who was responsible for this is walking freely without any guilt .""
But this will not entitle you to lodge a complaint against him. You can consult a doctor for treating your traumatic issues.