A plea deal gets you a lighter sentence, so coming out against it now is not a good look and will bite him in the ass if he ever has trouble with the law in the future.
That's not what happened. Johnson became president when Lincoln was assassinated and at that time the president and VP didn't run on a single ticket and instead the VP slot went to the presidential runner-up, who, of course, was from the opposition. So we didn't really elect Johnson; we elected Lincoln, but John Wilkes Booth happened and he fucked us for generations.
It doesn't say the exact opposite, that's why. Your question is a non-sequitur.