DKDK Quadrant

Based on the "Metrics of Knowledge" Quadrant. (A) What you know that you know (B) What you don’t know that you know (C) What you know that you don’t know (D) What you don’t know that you don’t know (DKDK)

He keeps saying the problem is with the plumbing, but I don't think he knows that he's not a plumber. He's stuck in the DKDK quadrant.