So was NOT trading Vazquez, that was epically awful.
If you assume they knew about his legal issues, then yes. But I don't think they did. So they had one of (if not the) best relievers in baseball, at a cost controlled rate, in his prime. They wanted a big piece, similar to what the Yankees demanded for Chapman. I don't think they were wrong to hold for that, from a baseball perspective.
And I think that if they had known about his legal issues, MLB would have slammed them for acting in such a dubious way.