What are my options? This is a care/POA/post. I am sorry for the length of the post but please read, I need help.

Hello,
I’m past the point of trying to fix this with doctors. I need legal advice, past experiences, and potential strategy ideas. Thanks for reading:
My mother is stealing all my father’s medicine.
My father is 83 and has had the world’s worst luck in terms of health the past 15 years. He has had two knee replacements, retina surgery, an emergency triple bypass (was rushed during a routine checkup) and a near death GI surgery which was misdiagnosed and had to be airlifted to UofM. They ended up cutting out about 20% of each intestine, tying what was left, and sewing him back up. With each surgery came ALOT of opioids. As soon as he’d recover, he’d suffer another emergency, and more pain killers. By the end of the run-on bad health, he was chemically dependent on them. I will not say addicted, because he wasn’t abusing them. It was almost as if his brain chemistry was stuck in reverse. Functional when under the influence of his pain meds but a zombie when they were gone. He started to run out 1-2 days early each month and over 6-7 years it became about the last half of the month. This is where my mother comes in.
My mother is 61, she has always been a busy woman. At the time his meds were running out she was sick of the monthly withdrawals, the requests to call the doctor to get something else, fed up with his surgeries and the recoveries. At one point she even said, “you better hope you don’t need more surgery cause it’s not happening.” Her solution was to exaggerate her new knee pain and get her own Percocet prescription as a “supplementary” prescription. She would pick up my dad’s meds from the pharmacy and administer them as she saw fit. Could be more, could be less, but not as prescribed.
Fast forward to 2024 and my mother’s knees are both bone on bone, she has a meniscus tear she won’t deal with, and very bad arthritis. She has had several vomiting episodes, maybe 2 a year that last 3 days and always result in an ER trip. She disregards everything the doctors say and claims they are morons, and she knows more. She’s very smart so she can be believable. About 14 months ago I began to suspect foul play. I suspected she would blow through hers and then dip into my dad’s bottle. He always backs her up, but he finally broke down to me. He doesn’t enjoy the euphoric feeling or any drug, he never has. But his age and his lower back he cannot move. He has been going from the couch to the computer to bed and he’s miserable. My mother on the other hand was zooming around the city.
7 months ago, I found a phentermine pill on the kitchen floor. 5 months ago, I found a letter from their pain clinic. It was addressed to my mom, and it stated they were cutting her off due to a drug test which showed high levels of Phentermine and Benzos, neither prescribed.
There are ALOT of asserts and money involved but it is extremely unorganized. My father averaged 6 million in income and retired during the housing collapse. My mom is now selling a lot of the assets and not keeping up with the rental portfolio. The family business was failing to the point that I left to join a corporate firm. She is taking 100% of my dad’s pain meds. Gaslighting my siblings and scapegoating me. Please remember she is brilliant in mental warfare (as all narcissists are because they must trick themselves first).
I do well for myself, so I do not really care about the assets and monetary accounts. I want to protect my father because he’s miraculously in good health outside of his pain. He will not confront her or stand up for himself. She keeps the rest of the family at bay and gives them houses and pays for their kid’s college. Even if they believed me, they won’t stand up.
I’d like to help my mother as well but don’t have 4000 hours to spend on her therapy.
I am 32, fully independent, and have a very fortunate income. I have no financial motives.
What are my options? Time to lawyer up? File elder abuse charge? Force rehab on my mother?