If he were really against Putin, his outrageous rhetoric would have gotten him in real trouble.
Zhirinovsky is allowed to say almost anything to defuse the situation and be known. He has predicted fraud in the election i.e. that he will only get 15 % although he should have 30 %.
https://newsland.com/community/4765/content/zhirinovskii-predskazal-masshtabnye-falsifikatsii-itogov-prezidentskikh-vyborov/6127769 The name of his party Liberal Democratic Party of Russia is as well a joke.