I checked the news around deadline time and there was no official news that Zverev retired, I could see his announced match on Flashcore and other websites with preview.
Trofo and cryptofrka will have the final saying. I just wanted to say that we had similar questions that remained valid. Besides, there is always an option that a player can withdraw from a tournament so maybe someone could have expected this after Zverev played five sets in the final of Roland Garros tournament.