Yeah, I didn't get that shit at ALL. Matt promising that Dylan would never fuck up again, I can see that (surprise, surprise, white dude Dylan gets off with a stern warning not to do anything bad again or else then he'll be in trouble, as punishment for a crime that would probably have gotten a black man thrown in jail for years, at best). But "owning one" to the DA? The fuck? What can he even owe? How can he repay that? "Next time you have a client who may or may not deserve jail time, I get to throw the book at him and you have to accept it"?
On the Jesse thing, Jesse didn't actually defend Dylan, I think he just offered Dylan some advice about pleading guilty or whatever, and I remember Jesse actually being happy for Dylan for whatever the outcome was of that situation. It was Steve that Jesse yelled at about not recognizing his white guy privilege, thought he also wasn't defending Steve and was upset that his Mexican client "be gone, he be outa here!"