Murder? Slander or VAWC

TLDR;

- My father died of heart attack due to neighbors actions
- the night he died our neighbors had a shouting match with us (same people who caused my father to die)
- They're trying to sue me of either oral defamation or VAWC due to the words I said to them that very night.

My questions are:

1. In my father's case, was it Homicide or Murder?
2. What steps should I take for counter-charges?
3. What specific charges can I file against them?

Please help.

---Long Version---

Good day,

My father died recently due to an altercation with the uncle of my mom who is already 80 years old. The old man had issues with the on-going modifications that my dad planned for our house. The only thing is that the old man drew a 'bente nueve' or a balisong out of his back pocket, pointed it towards my dad and tapped it violently against our gate (my father was inside our premises) shouting "Lumabas ka dyan! (Come out here!)  basically challenging my dad to a duel. My father walked back towards the main door of our house and had a heart attack. The old man then proceeded to shout "Mamatay ka na, Mamatay ka na!" (DIE! DIE!). My father after us rushing him to the hospital, died shortly after.

My mother asked me to wait at the morgue with my father's body while she went to the barangay office to file charges/blotter since I was insistent that I want to go home and confront the old man who at the very least had a direct/indirect  hand with it. Clearly my mom knew that I was in a very angry mood and tried to calm me down. She knew that I was very, very, mad not only to the fact the my father died, but that it was my birthday a day before he died. It really, really, really hurt so much.

Later that evening, when we went home from the morgue, my mom expressed her grief by shouting at the old man "Kriminal, walang hiya ka!" (Criminal! Have you no shame?!) when the old man's daughters (two of them, approximately 20 to 30 years older than me) promptly berated, shouted and bullied my mom. Since I heard the commotion upstairs, (I was at the 4th floor of our house, and I returned home a bit earlier than my mom, probably 5 minutes early, ), immediately rushed to her side since I knew she was in a "fit of anger" due to our very recent loss, and tried to pacify both her and the neighbors I said to them, "tama na po, namatayan na po kame", the neighbors didn't stop and continued to berate my mom, me and my sister, calling me "baboy", and "piloko" (addressed to my body size and my college course and previous profession) and called my mom "boba".

The neighbors said to my mom "Kasalanan mo naman kung bakit namatay yung asawa mo, hindi mo kasi inalagaan" (It was your fault as to why your husband died, due to your own neglect). My mom broke down, cried and held her chest. I knew I had to do something for them to stop since they don't listen to reason and had no utter shame on what kind of damage they already brought to us that day.

That was when I said something to which, I agree was really hurtful. My intention was to take their attention away from my mom since it was my duty as her son and to my dad whom  cannot protect my mom anymore. Seriously, their words were like bullets to my mom. She really was not "mentally and emotionally sound" that night. For all I know my mom could have dropped dead that night due to "sama ng loob", let alone her illness and they just wouldn't care.

After me uttering the hurtful words that slipped out of my mouth, they returned what I said and directed it towards my dead father and my sister. Which until today, I find very offensive since it was directed to someone who already died.

The only words that stopped them at that point was when I said  "Magkikita tayo sa korte!" (I'll see you in court!). To which they again took offense due to the fact that their brother was already in prison due to an illegal drug related case. My aunt and my sister was pushing me towards the door of our house and closed it. Effectively ending the shouting match. They still talked crap in front of our house for hours.

We of course, filed a case already is waiting for the subpoena to be released. We were advised to wait at least 3-4 weeks to know the date of the hearing and who the judge will be. The police officers deemed it to be homicide since there was no physical contact/injury between the old man and my dad on that day.

Now, almost a month after my dad's death, these neighbors went to the barangay office and is trying to file a case due to either oral defamation or violence against women and children. They're saying that they were offended of what I said that night.

My questions are:

1. In my father's case, was it Homicide or Murder?
2. What steps should I take for counter-charges?
3. What specific charges can I file against them?

I need help and to be honest this is too complicated for me to comprehend at this point. I have had trouble sleeping at night sometimes.

Any advice from the pinoylawyer.org folks is very much appreciated.

Thank you in advance and God bless.