I can’t remember exactly what I said. For me, the bottom line was that we had talked about how this transaction was supposed to go down, literally since they were teens. Ds2 understood completely; ds1 kept acting like there was ambiguity. There was no ambiguity. None. But it showed how tight ds1 is around money, which we all knew, but it never occurred to me that he wouldn’t pay up when the time came. And, of course he would pay – he loves his brother and would never stiff him – but it was uncomfortable for everyone that he let this drag out for months and sometimes you just have to provide a kick in the pants to people who are slow to act. It kind of reminds me of how OP talks about her older son “taking advantage” and how if you don’t just confront an issue it can linger. I felt like it had lingered long enough and that ds2 had asked repeatedly about it. I reiterated AGAIN the expectation, explaining again how it was supposed to go down and that I expected it to go down just like that and soon.
Yes, you’re correct that younger brother said not to say anything. That might change things, but I don’t think I’d get in this situation because I wouldn’t agree to not say anything, especially if they have put me in the middle. If it were me, I would text both boys and say I feel caught in the middle and that they need to figure it out. How they do so is between them.