When Zim invokes Mr. Dubois to shame Johnnie, he reinforces the teacher’s position as one of Johnnie’s father figures. While he related Hendrick’s punishment in detail, Johnnie is sketchier about his own, generalizing what Zim, Captain Frankel, and Major Malloy say to him. This could be seen as showing shame for his actions or expressing distaste for recalling this event, but it’s also possible that his attention is limited until he understands the seriousness of his actions. Johnnie learned from Hendrick’s failure, and he takes responsibility for his actions, accepting his punishment without complaint.