I believe you are simplifying the problem of Puting being the ruler of Russia and the actual factors which keep him in his position of power, though. Russian propaganda, as any other kind of propaganda, adapt to continue to keep people oppressed and picture the leader and the government as superior, not matter what the adversary does in the west.
I live in Russia and I am sure I am right. Ispiring the hatred to the West and to Ukrainian's Maidan in necessary for keeping the people believe that a democratic revolution is a bad idea.
Russian people will not experiment cognitive dissonance, because the Klemlin won't simply broadcast policies done by Trump which contradicts their discourse, they will continue to give a spotlight and cherry pic whatever Trump and the leaders of Europe do which goes along with the official discourse of the Kremlin.
I believe it is almost impossible for Putin to make Russia more isolated for preventing the Russians to know such things. Besides other reasons, there are a lot of hidden oppositioners everywhere, including the TV, which will use any possibility to broadcast such information.
Also, Putin is authoritarian he does not care whether the population experiments contradictions, he will stay in power by force of he believes it is necessary.
If the rating of Putin decreases, any general will easily overthrow him and become a national hero.