Please pray for guidance - son has become aggressive and stopped studying

As-salamu alaykum sisters, I'm writing on behalf of my 45F mother - I'm her 17F daughter. Please forgive any mistakes, I'm just desperate for advice and dua. My 20M brother has failed all his classes. Our father passed away in 2022 from lung cancer and after that he stopped caring about school. He spends most of his time at our aunts', plays games all day, and has become very aggressive and violent - fighting with his sisters and cousin, even chasing them with an axe. This kind of behaviour wasn't new, but after our father's death, who was the only one he ever listened to, it's gotten much worse. He is irresponsible and once got involved in a scam where he gave people access to his bank account; it turned out to be linked to drugs and the police had to step in. He is in his third semester but failed all his first-semester classes and now barely goes to college. When I or our mother try to speak to him about it he becomes violent, says hurtful things, breaks things, punches walls, and has hit me and our siblings a few times. When confronted about failing, he even told our mum to cancel his admission. He spends time with kids younger than him and refuses therapy - he won't agree to go. We have tried a lot already: 1. Talked to him many times - our family usually has open communication and we've been vulnerable with him. 2. Been gentle and patient. He's been babied and given lots of things, and that may be part of why he avoids responsibility. 3. Got outside intervention from relatives and male role models who advised him, but nothing changed. 4. Tried motivating him and spending quality time together, still no change. 5. He's opposed to our mother remarrying (she doesn't want to either), saying she would interfere in his life and 'hold him accountable' - his words. We're a single-parent household now and it honestly feels hopeless. Please make dua for us and, if you can, share any advice from those who have faced similar situations - how do we protect the family, get him to accept help, or at least keep everyone safe? We're worried for our safety and his future. JazakAllahu khair for reading and for any guidance or prayers.