Please listen to Aunt BigHeadBertha for a sec here. I am also estranged from family and remember, there are very good reasons for that.
Therefore, my advice: Do not, I repeat DO NOT get drawn back into any of their stupid and toxic BS, which of course is exactly what this is. It is the type of thing you left over in the first place. Lack of respect, badmouthing you and etc. Am I right?
Yes, it was rude and nasty of him to include you in his memoir when you told him he didn't have permission. And of course he misrepresented you. That is because he is a rude and nasty person, just like the rest of them. They probably didn't like their scapegoat to leave. They want to keep bothering you anyway. Don't let them!
Yes, it's possible that you might be able to pay a bunch of money to an attorney or some such to make him retract it or go to the publisher and get drawn into a bunch of ugliness to make him retract it.
...And that would entail going back into that hornet's nest and dealing with the crap you've already, smartly, left behind.
I will tell you this, no professional publisher would have let him get away with that without releases from the people he's talking about. Real publishers are far smarter than to set themselves up for lawsuits. See, the whole thing is tiny and stupid. Also, people don't believe everything someone says anyway. He is most likely just showing everyone what a jerk he is so there's really no need for you to step in at all.
My advice is to throw the copy away or delete it. Let your stupid brother have his stupid little memoir and show all two or three of the people who buy it what a jerk he is. Who cares?!
Do you care? No, you do not. Because you have already moved out of that garbage dump and onto better things. Don't waste another minute thinking about what some ill mannered dimwit said about you. It doesn't matter. Just stay away from him.
That's my advice, anyway. Now I hope you will go have a super excellent week and treat yourself very, very well to balance out the dose of toxicity you've just been dealt. Best wishes, dear. :)