Any responsible adult in that situation would realize that "the buck stops here" -- that is, with the person who had the ultimate responsibility to make the decision, regardless of who else was involved in the process.
I'm sure Donald Trump would have gone batsh!t crazy -- and rightly so -- if one of Trump Jr.'s real estate projects was running into trouble and the kid blamed all the problems on a deputy project manager.
That's the only way any responsible leader in an organization works. Otherwise, you end up in a situation where the chief executive rants for days about how ineffective one of his senior managers is, while everyone in the organization wonders why the lunatic doesn't just fire the guy.
Oh, wait a minute ...
LOL.
I can see Trump’s POV. If Sessions presented Rosenstein as the guy he really, really wanted as his Deputy, Trump may have felt that Sessions deserved that pick. Then Sessions and Rosenstein did a Texas two-step, and Trump’s administration was thrown into a sh!t show of monumental proportions.
You may see Trump’s venting as wrong. I see no issue with dealing openly and honestly with issue. It’s just two different takes on the same situation.