Who knocked over the comic books?

In chapter 15, page 158, some comics slide off a shelf and fall to the floor. Aech suggests that was nothing more than a software glitch, but Wade is worried. He thinks that maybe an invisible avator is in the room with them and accidentally knocked the comics off the shelf. "No way, Z," Aech tells him, "you are getting far too paranoid. This is an encrypted private chatroom."
The incident is forgotten until chapter 33, page 313, when Ogden Morrow surprises Aech and Wade by suddenly appearing to them in the private chatroom. He tells them "I've been eavesdropping on the four of you for quite some time." He says that his avatar has special powers that allow him to enter chatrooms undetected and admits it was him that knocked over the stack of comics earlier in the novel. "I can be pretty clumsy at times."