Issues with private pay caregivers taking over in our family home!

We hired a husband/wife in 2018 to help at my Dad's home. Dad's drivers license medically suspended after minor car accident. Dad has cognitive decline & dementia (mid stage now) & lives in home I grew up in. My Mom passed 2016 after 8 HEARTWRENCHING years of dementia. The husband asked to cut grass & do maintenance. He's great in Summer when tons to do outside. Over Winter I wanted accountability for the 24/hrs week he was paid. His wife was brought onboard (by my older brother who is POA) months later to help oversee other female caregiver helping on their days off. I set up EVERY detail about Dad's care, house projects, etc. I live 1 hr from Dad & went down EVERY wkend for 8 months until I was burnt out, mostly from being SO agitated at my 2 brothers (1 older who lives 8 hrs away and 1 younger who lives 1 hr away near me) At that point, they were not seeing my distress & I felt my only option was to say "I'm done" to get them to engage. So, they pulled the rug out from under me & starting removing me from my Dad's care & all the communication about what was happening at the house. It's important that you know that ALL I WANTED was for them to pitch in more as I was doing TOO MUCH!! I am a classic middle child, very detailed & proactive! After a few months of trying to focus on myself again I continued to feel compelled to care for my Dad & slowly started getting involved with details at the house again. All the while, being told that I should not give any direction to the caregivers or interfere with what they were doing. What has followed in the months since is I feel this couple has crossed a line & taken control of our family home in a way that makes me uncomfortable to visit my Dad. The wife does all kinds of passive/aggressive stuff towards me. She moves things that I have in special places, they have said that if I come back, they will leave. All the details I set up, she slowly started to change, I feel she's always trying to one-up me, she takes papers home that should be left at house, I found out she was monitoring when I called my Dad, and from another room she actually took her phone & recorded the audio of my Dad talking w/me. I am very territorial of my family home & believe there is a boundary you just DO NOT cross when you work in someone's home & she has crossed it! With my brothers approval they hired a new caregiver a few months ago who just weeks into working at the house was caught on camera folding up an envelope that had my Dad's return address on it & shoving it down her shirt (right infront of security camera that she knew was there )& we found out she had made letterhead of it & had written a letter lying that she had worked at the house for 9 mos when she had only been there 2. Isn't that FRAUD?!I called my Dad's lawyer who actually said, "at this time, I don't see that as grounds for termination" ARE YOU KIDDING ME! I wanted to fire her *ss but both my brothers wanted to forgive her & keep her. I asked them if we had someone better in the wings to replace her would they fire her...they both said yes, YET, keeping her was easiest thing for them to do. TOTALLY unacceptable but what was I going to do?? So I've been monitoring the cameras for the past months which allows me to see issues w/caregivers but most importantly have eyes on my Dad who's home alone 14hrs/night. He's declining & it's vital to watch him closely to know when overnite care is needed & gain insight to share with his various docs. One night, I happened to check the cameras & the carbon monoxide alarm had gone off & I alerted my brothers & called the fire dept (who told us that if we hadn't noticed this our Dad would have been dead by morning. Husband/wife again saythey don't like my oversight & will quit if it continues. My brothers called today & want to remove cameras....NEED ADVICE!