Kylo doesn't try to speak. Unlike Rey, it's not that he can't. It's just that there isn't anything to say that would be at all useful. It's obvious that Rey isn't in a place to talk.

He doesn't pause to ask her for directions once they get back to the apartments, either. He knows which one is hers; that information wasn't difficult to figure out even if he'd never had occasion to make use of that knowledge until now.