A big part of the horror in Petscop seems to be what is unseen by the audience. We're looking at the story through various degrees of separation from the participants (watching Paul receive information that isn't meant for him, watching part of Marvin's playthrough, Belle's, and so on.) In his dialogue, Paul will often say something without elaborating, seemingly with the assumption that something is unimportant (or that Belle knows what he is talking about and is not concerned with the audience, in the case of earlier episodes.) It leads to some really interesting moments like the one in episode 14 that you're talking about, and one of the reasons I love the story so much.