He's so taken aback by the bag-headed giant's reaction to his apology that he ends up with the conclusion that the best reply is not to speak to him again.

In context, it's easy to do. As relieved as Epsilon would like to be about the speed with which Ginko responds, he's extremely unenthusiastic about its cause--not to mention the sight of just how deeply these same vines bruised Ginko's throat just days ago.

His grip on the steaming vine tightens, his fingers pressing into the still-hot splits in its wood.

Which turn out to be a few inches deep, and wet with sap and oils.

"I'm not sure--but Ginko, your neck."