Dear Gill,
I am in tears for you, what an awful situation, and one we haven't had a lot of here on TP recently, but that is not to say you are alone as some carers won't like to admit they have a problem with a drunken brother - so congratulations for being sensible enough to face it. And as my dad had a drunken brother I do know what chaos this can produce.
However, my tears won't help so here are some thoughts, not very joined up I am afraid.
I know of no reason why SS should not speak to you about your mum, there is no such thing as a "Main Carer" other than for claiming Carers Allowance which it seems he is doing for his beer money and not for the caring. Seems as though his partner would be more entitled to that but she probably can't claim that as well as DLA. Being an "Appointee" is a term that the Dept for Work and Pensions and the Attendance Allowance people use to communicate with someone regarding a person's state benefits. That doesn't have any legal status either apart from with the DWP. It doesn't entitle you to much else. It is a pity you haven't got a Power of Attorney but the "old" style of POA only gave you control over money and you seem to be pretty much in charge of that, though £60 a week should be more than enough for food and toiletries for your mum, cleaning stuff etc. Why are you giving that much to your brother and his partner? Tell them you can't afford as much in future. Ah, easier said than done, I know. But £30 or so should be enough for your mum on a weekly basis.
I would first suggest you go and see her GP if the SS team is such rubbish. The GP can be quite influential and they see a lot of life, so he or she might be a good place to start. Make an appointment in your mum's name, don't say who you are when you book it, just turn up and tell your story - and take the mobile recording with you.
How about getting your mum some respite care in a home for a few weeks? Your mum might actually appreciate the feeling of being safe and not in the middle of a permanent row, and then be more accepting of going into a home permanently. Of course, that might not work, but it is surely worth a try. It actually sounds as though she is getting to the stage where a care home should be considered anyway, despite your brother supposedly caring for her.
As others have said, the situation regarding money and benefits appears to be illegal, but I don't think shopping him is going to benefit your mum, it sounds as if he will become even more argumentative and possibly violent, and you don't want your mum in the situation, so maybe the respite is a thought. In any case, shopping him is likely to take months before anything is done given the red tape with government departments.
Very few of our relatives want to go into a home or leave what they regard as their home, but in the event many of them have to for various reasons, but fear for their safety is surely a strong reason.
Your problem seems to be convincing the social services that she is at risk - which she is. Can you take your mobile down to them and play them the conversation with your brother's partner, and perhaps record a couple more that show what the situation is?
Though again, I am not sure what they can do as he seems to be there with your mother's agreement. Though you say you pay the rent? Does the rental agreement allow another family to be living there? Which is what your brother and his partner effectively are? Could the landlord help?
Boy, it is getting complicated for ME to deal with, I don't really know how you are coping, Gill.
One way or another, you have either got to get him out of there or get your mum out, and it seems to me that he isn't going to go without a fight, and if he is drunk I wouldn't like to think how such a fight might end up. I would say you are all at risk, including his partner, but she has a choice, your mum does not at the moment.
Now, another thought, I don't know what job you do, but could you afford to take a few months off without pay (and would your employers agree and give you your job back after?) and go and stay with your mum for that time? Employers are supposed to be more supportive these days. You should be able to claim Carers Allowance yourself then - never mind your brother, he isn't caring for her, you are - and your mum should be getting some rate of attendance allowance. Maybe you could get a part-time job near mum's on a temporary basis to add a bit of income while you are taking time out of your normal job. Somebody I know charges £15 a day to look after pets in the home while people are on holiday. She only spends an hour or so - not bad pay! And probably cash in hand, though as an Accountant myself I shouldn't mention that. But everybody does it.
By the end of the, say, three months, you might have had the chance to get your brother off the scene and your mum into a situation where she can get a proper care package to help her out, or even into a care home.
You talked of giving up your own job, and some people do, but it sounds as if you need yours, not just financially but mentally as well, so don't give it up unless it is a last resort. I get the impression that even if you went to live with mum, your brother would still be there kipping on the settee and still creating arguments.
I've run out of ideas now, tried my best, I think the GP would be my first call. Legal advice is all well and good but it takes time and it won't make your brother in a better frame of mind at all. I worry about the possible consequences from him.
Oh, you might also want to contact Help the Aged, or Age Concern, I think they both have helplines or help sections on their websites. This is not just an Alzheimers problem but one that could apply to any elderly person. Try them out. I've been in a position myself where I didn't know what to do about a problem (not to do with the elderly) and a charity's helpline was my saviour.
Let us know how you go on.
Much love
Margaret