I believe that's where Dreeben replied (from the transcript): "the specifics of the investigation were conveyed to us not on the face of the May 17 order but in interaction with the acting attorney general." In other words, 'Rosenstein SAID it was OK'.
There is ample evidence that Rosenstein approved the scope of investigation, and allowed Mueller to run the show against Manafort and his pre-campaign activities. Rosenstein produced a letter at least after the fact of the Manafort raid.
There is no evidence that Rosenstein objects to the scope creep, and Rosenstein was grilled on this point in open Congressional testimony.
I'm not saying I think the scope creep is okay, only that Mueller and Rosenstein are on the same page, and as far as Mueller is concerned, if his grant gives him the subject matter jusrisdiction, he has the subject matter jurisdiction. Jurisdiction as those clowns see it is "anybody who worked on the Trump campaign is fair game for a probe."
The Judge should subpoena Rosenstein. Make his state this in court.
I do believe the law stipulates that a special counsel needs to have his scope of operations and such in a WRITTEN document.
The Congress passed a law eliminating the Special Prosecutor after the Clinton Impeachment, and replaced it with a Dept. of Justice appointed Special Counsel law/rule, but THAT has specific requirements. It may well be that Rosenstein screwed up and failed to fulfill them; hence his 4-5 month later memo AFTER the Manafort raid.
Now it’s come back to haunt them. Verbal instructions are a violation of the law itself!