What does squealer say was the real MVP?

I'm not sure what you mean.... "most valuable player"? If so, I'd have to say Napoleon.

Squealer would talk with the tears rolling down his cheeks of Napoleon's wisdom the goodness of his heart, and the deep love he bore to all animals everywhere, even and especially the unhappy animals who still lived in ignorance and slavery on other farms. It had become usual to give Napoleon the credit for every successful achievement and every stroke of good fortune.