Mom taking advantage of 80 year old

Hi guys. Recently my mom (who is beyond toxic and a opportunist) took over power of attorney of my 80 year old grandpa. Since then she has open multiple credit cards in his name, bought cars, takes 1500 of 1700 he gets per month for social security. On top of all of this treats him like complete shit. I would say it’s borderline elderly abuse because she absolutely controls him and doesn’t even allow him to cook because she doesn’t like the smell of his cooking. It’s really sad to watch. Lately he says he wants to move in with me and my husband and son. And I’m 100% okay with this. If he moves in with me I will NOT allow her to do this to him no more. Does anyone have any advice for me and what I can do to not let her have this power over him anymore? Can I report her? Let me add that hes absolutely capable of understanding everything and is beyond healthy and can take care of himself, the only thing he can’t do is drive because of bad vision. Any advice helps thank you 🙏🏼 😌