The briefcases. Right after the cut back to the bar, you see Parker with both briefcases that half the episode followed.
Symbolizes Mattingly taking Parker's advice and following Parker's and the entire scoobies' Robin Hood routine.
The DVD order of the episodes differs markedly from the airing order, according to TheTVDB:
DVD 01/TV 01 The Nigerian Job
DVD 02/TV 02 The Homecoming Job
DVD 03/TV 07 The Wedding Job
DVD 04/TV 09 The Snow Job
DVD 05/TV 08 The Mile High Job
DVD 06/TV 04 The Miracle Job
DVD 07/TV 03 The Two-Horse Job
DVD 08/TV 05 The Bank Shot Job
DVD 09/TV 06 The Stork Job
I rewatched this to see if I could find any actual crossover between Hardison and his "players", but there's no explicit meeting.
He was in the antiques store when they arrived to check out the chest (and "found" the cipher), and he was also on the street after they came up from underground the first time, where they met Nate for the second time and Eliot ...
It would have to be an international agency with influence in the U.S. (to get Nate cleared of his charges) and in San Lorenzo (to provide the team with entry visas when they chased after Moreau). Interpol would have been a logical assumption at first, but as Chiffa said in her comment if it was Interpol then Sterling would have been involved, and he ...
As far back as Season 1, Nate and Sophie are seen to be effectively trying to "cross-train" the team. Instances include:
"The Juror #6 Job" in season 1, where they are trying to teach Parker how to be more "normal", and Sophie is seen instructing her in persuasion techniques
"The Stork Job" in season 1, where Sophie coaches Eliot in grifting techniques to ...