Need some advice, ideas or new ways of approaching this

I'm not even going to bother with the "I'm asking for a friend" bit

I'm hoping that someone can give me some advice, I'm dealing with a situation I've never been in before and I am unsure how to approach this.
I'll preface this by saying that I am getting legal advice but I'm hoping for some more advice in the meantime.

My father is currently unwell and is in hospital, he is looking like he will be there for the near future at least so I am dealing with his affairs while he is unable.

TLDR:
My Dad's ex is attempting to take possession of his house, on 2 separate occasions (1st 4 years ago and 2nd last Saturday) she has told a story to the Garda about wanting them to attend while she recovers her property from the house and then has attempted to take possession of the house. On both occasions I was able to intervene but purely by accident I was in the area and noticed the Garda outside the house and came to investigate.
While they did live together for years and she claims under the cohabitation act some rights over the house her name is not on the deeds, although it is on the mortgage, as they used the current mortgage to buy her an apartment that she owns outright.
This latest time they got in they stole property of mine (since returned), attempted to steal keys to the back door, rigged the back gate so it could be opened later on, damaged the security camera at the front door, intimidated the tenants, threatened to evict the tenants within 7 days, threatened to change the locks on the tenants and more.

Full story:
My parents bought a house back in 1985, in 1987 they separated and in 1989 the deeds were transferred into my Dad's name solely.
A few years later my Dad got together with his partner and everyone lived happily ever after ... for a time :D

My Dad and his partner separated some 7 or 8 years ago and about 5 years ago she started proceedings under the cohabitation act to gain an interest in the house. However, nothing ever happened with that case (I am not sure as my Dad was dealing with it and his memory now is very bad).

A little context: My Dad has had 3 strokes and 2 TIA's in the last 5 years and his vision, memory and comprehension have been severely affected. Getting information from him now is quite difficult.

There is a mortgage on the house in both my Dad's and his partner's names. That mortgage was used to finish an extension on the house in question and the rest (the majority) was used to buy her a 3 bed apartment under her own name solely and that was the agreement at the time, she would have the apartment in her name solely and he would have the house in his name solely. And no, that I am aware of there is no documentation to prove this.

After my Dad's first stroke, he was in hospital for 3 months, she attempted to take control of the house and seems she recently found out that he is not around again and attempted the same. On both occasions she has gone to the local Garda station and asked them to attend while she recovers her property, for her safety (in fairness, for the Garda, a reasonable request) but once she gained entry into the house the first time she said thank you to them (as it was empty) and they left. She then took most of her stuff but loads more including the 40 inch TV and a bunch of other stuff, plus loads of paperwork of my Dads. When I found out what has happened I luckily arrived when they had temporarily left and I fixed the door and changed the locks and they were out.
This time they used the same ruse with the Garda but what they didn't expect was my Dad's tenants in the house (renting 2 rooms to help pay his mortgage as he cant work any more because of his health) and that is when they said that they were not leaving, that the house was hers and she was kicking out the tenants. I had been working on fixing some things in the house that morning and I had gone out to get some things to finish to I arrived about 2 mins after all this started this time around.
I explained the situation to the Garda but there was no resolution for over 5 hours. Finally an Inspector came down and we came to a compromise. The compromise was that she would get 1 of the 2 keys needed to get in and the Garda would have the other and we would prearrange a visit for her to come back and get her stuff as long as the Garda and myself were there.
The reason we had to reach a compromise was that even though it is my Dad's house, even though I have Power of Attorney I had no copy of the deeds and there for could not definitively prove she was lying. (Oh, I have all that proof now).

For most of the time, because when I showed my face her family (there were 6 of them btw) would start shouting and getting aggressive the Garda asked me to initially stay outside in my car and later to stay upstairs it seems that the Garda just let them run riot so in all of that time they attempted to steal keys to the back door (tenants noticed this and stopped them), rigged the back gate so it could be opened later on (I saw that from upstairs and fixed it later), damaged the security camera at the front door (I witnessed this), intimidated the tenants, verbally threatened to evict today and later threatened to evict the tenants within 7 days in writing, threatened to change the locks on the tenants and the list goes on.

I have requested a meeting with the local superintendent and he is passing it onto the inspector for me to meet and discuss with them how to proceed but they keep telling me its a civil case.

Advice on how to proceed...
Do I press charges on the theft and the criminal damage of the cameras? Or his this just going to make things worse?
Do I get a barring order to stop them from coming back? Or is this just going to make things worse?
Is it not illegal to lie to the Garda and to use them to gain entry to a house you do not own? I would have imagined that it can't be legal to do that.
Any advice on how to stop this from happening again?
Anything that you can think of that I am missing?

I am also sure I've left things out or explained them too quickly you don't have all the background info that is in my head. Ask questions if I need to clarify anything.