I believe this part was a detail included to make the viewer believe that Dex was actually running, after the reveal last season when Deb saw him kill Doomsday. Without knowing the events leading up to, viz that he was trying to find the airport mobster and that the nerdy guy had actually cancelled the cards... it instead makes you assume, the cops/Deb had the cards cancelled and it's screwing up his plans to run.I am really confused about the credit card thing. So, the intern cancelled all of Dexter's cards, and Dexter now knows they have been cancelled, but he showed/expressed exactly ZERO concern about that. He just moves to Plan B and uses cash, but shouldn't he have at least suspected that Deb figured him out and she/the police had his accounts frozen to prevent him from running?