How did you come to this conclusion if you already admit Brother & the Dominicans had no connection?
Why would the Dominicans care if he do or didn't "do right" by brother?
Brother's well-respected in New York.
Basically, everybody in the business knows each other.
Just like in season 3 when Brother was asking Vincent about Omar.
Vincent isn't connected to Omar, but he knows who he is.
When Brother asked him:
"Are you down with this nigga?"
Vincent said something to the effect of:
"No, but you can't be in the game and not know who he is."
Similar situation with Brother and New York.
When Omar shot Brother and Brother went back to NY, word got back to New York and they knew what went down and why.
Now, whether Brother told them directly or it spread by word-of-mouth.......they found out because, well.....again.....they're all in the game.
It's just like if someone you know and respect doesn't fuck with somebody..........chances are you're not gonna fuck with them either.
If for no other reason than the fact that you know how that person gets down and that.......9 times outta 10......if they're not fucking with somebody...........it must be for good reason and you'd be wise to follow suit.
That's what this whole situation with Brother is really about.
We can even break it down to
@Duwop being well-respected in his neighborhood.
Like when some younguns were blocking his driveway or something and they realized it was his house, they moved their car out of the way because of Du's standing in the community.
Now, from what I understand, DU wasn't connected to those dudes in any way.........but they just had that level of respect for him to move their car.
Same/similar dynamic with Brother and New York.