Ben Zobrist, because he is a creepy weirdo and nobody invited him. Justin Grimm, because he is stupid and he spaced out and forgot about it. And Javy, because he didn't know where the party was at, so he went to the front desk to ask if they could tell him, and when they asked him for the name of his teammate, he hadn't bothered learning Dexter's yet, so he was left in the dark.