Can anyone advise me on what to do? I think I need a legal document outlining the disbursement of (lawsuit about abuse of parent) proceeds with sib.

Yes, meeting with brother and attorney to make a documented plan of how any funds remaining from settlement after mom passes will be distributed makes good sense. Try to stay calm, let attorney do much of the talking. Brother may feel threatened at first - that you don't 'trust him' to 'take care of you'. Life circumstances change, he might become ill or die suddenly. No harm to getting on paper by an attorney. Try not to back him into a corner - give him room to 'save face'. But not enough room to wiggle out of his agreement to you.
If he gets all upset at this meeting, get him to agree to come back in a month to discuss it, once he has had time to think about it.
His reaction to these first meetings will tell you a lot about his willingness to share, I think.

Floridagirl - so thinking through this - I'm sure you realize it - but wanted to put a fine point on it. Does your mother have a will in place? As gently as I can say this because I know it is painful, your brother's POA ends when your mother passes away. He has zero control over her money at that point. Even if he is the executor of her will, he is only legally allowed to distribute the contents of the estate as they are written in her will. So if her will says that her estate is to be split between you - then you will get your part of what is left of her estate after all of the bills are paid.

In essence that means that you would split the remainder of the proceeds of any lawsuit, you would have to sell any property that she owns and split the proceeds OR someone would have to buy the other out of their share. But your brother would have NO control over her money at that point.

While he is POA he can only execute the use of her money on her behalf. Once she is gone the POA is over with.

Any money she might get after she dies would be paid to her estate and it would be disbursed as outlined in the will.

Dead or alive, it's will be her money first, then be distributed to you and your brother based on her will.

My mother's homeowner's insurance company just notified me that she is due a refund for six months' worth of premiums they didn't reimburse us after we sold her house in July 2022. My mother has been dead for almost two years, her house was sold almost a year ago, and I WAS going to close out her estate this week with her final tax return. Now I have to keep one account open in her name just for this silly check to be deposited into, because they won't make out a check to me as her heir and trustee. Once it clears, I can then give half to my brother and keep the other half, THEN close the account once and for all.

You have no legal standing here unless there's documentation. You can have a contract drawn up now for you to be her paid caregiver with your expenses and salary covered retroactively. If your brother is a good guy who meant what he said, he'll sign it.

If he's not, you're out of luck. As you say, money changes things. The fact that he's already defaulted on paying you is a bad sign, so talk to an attorney asap.

What proceeds?
You haven't WON any lawsuit, and the lawsuit is done on your mother's behalf, not yours.
Firstly, any suit brougtht for neglect on behalf of your mother must be brought by her POA on her behalf and with her funds. And any recompense won goes to the mother, not to you two siblings.
This is all a mess as you describe it.
You expect money to be given to you now when you had a contract for payment which was not made. If he didn't pay you then, why would he now?

As to this lawsuit, I doubt you will win over attorneys for nursing homes which have deep pockets and can fight on forever. Just my guess. They will likely say that as you were there daily, and didn't like the care, you should have removed your elder to another facility. Just my guess. Who really knows.

In any case, it's way too late to expect payment from someone who denied it to you for years, and to trust that same person NOW with this seems that you are slow at learning the lesson brother has given you over time.

Again, any compensation in a lawsuit would go to your mother for any wrong doing by a facility, not to you two siblings. And only a POA can bring a suit on someone's behalf, and he is paying for that suit from her funds, which imho may be a waste of them.
You should see an attorney to answer your questions and give you your options.

While I do understand that you went to bat for your mother to document the neglect in the facility and the additional care that you had to provide as a result - I am curious as to why you believe that you and your brother will be the ones to receive the money.
Your brother, as the POA, would potentially receive any (potential) money on behalf of your mother - so I guess technically he would have "total control". But he has a legal obligation to manage your mother's money FOR her. It all has to be documented and above board. And for your mother's care. Period. That money is for her benefit.

I'm not sure I understand why you would have to negotiate for any money that you "want". If you and your mother have a caregiver contract in place, or you and your brother agreed in writing to pay you out of her estate, then you would be owed those funds certainly. But if there is some kind of potential "windfall" from a lawsuit, neither you nor your brother would be the beneficiaries of those funds as long as your mother is alive.

Then if I'm understanding correctly - it sounds like you removed your mother from the facility 3+ months ago. Was that at the behest of hospice? Of your brother? Or was that a decision that you made and then she went on hospice? Was the agreement to pay you $200 a week made once she moved in with you?

Is this something that you and your brother have sat down and talked about or are the problems are just stewing under the surface and not being dealt with? Often we push things under the rug and don't deal with them and they fester. And you are correct, money often causes problems. And promises are easy to break. Written contracts are not so easy.

I'm also not clear on what you mean by "He has promised he will always take care of me". I'm not really sure what you mean by that. I have found that often people pin their hopes and futures on things like an inheritance or family money or family providing for them in some way, and it doesn't work out the way they think it will. From your profile it sounds like your mom has needed care for at least the last 5-6 years. Based on the age of your daughter I'm going to guess that you are roughly my age (50s) but I could be wrong, You may be older than me. But I'm going to assume you may not be retirement age yet. And you noted in your profile that you are a single mom. So I'm going to make the leap that you have either had to keep working and taking care of her or had to give up your job to take on the care of your mom? If that is the case, have you had the ability to prepare for your own retirement? Or is there an expectation that there would be some level of assistance from the family or something of that sort in return for being her caregiver to assist with your retirement?

To often, especially daughters, end up sacrificing their prime work years and giving up jobs with the hopes that the rest of their family will see value in their sacrifice, and while the family may see value (there are many reasons why they may or may not - from preferring for their parent to be in a SNF to not wanting their sibling to take on the responsibility/not asking them to take it on) they often don't follow through with the promises they make to provide any kind of monetary support in the future if it is requested or needed. Or they don't make the promises and it may be expected anyway.

I guess what I'm saying is that you need to talk to your brother and figure things out. Because people often make promises in the heat of the moment that they don't even realize they have made. Deathbed promises. Promises under stress. He needs to know your expectations.

AlvaDeer, I live in Florida and our lawsuits on mom's behalf have met all deadlines, statutes of limitations and the like. If mom passes before, they are completed they will indeed continue on for the duration. In situations where the defendants contributed to the plaintiff's passing, they can be sued for both "wrongful death" as well as "survival action". If their actions didn't contribute to the plaintiff's passing, they can be sued as "survival action" for damages that occurred up to the time of passing. Thanks for your response!