James Caan, in his final film performance, was in a wheelchair and on oxygen throughout the filming as he was suffering from late-stage COPD and cardiac failure.
When Charlie accesses his stash of cash and weapons from the air conditioning vent in his house, he holds one of the pistols and looks upon it fondly before putting it back. It was a Walther PPK - James Bond's gun of choice. Pierce Brosnan (Charlie) played James Bond from 1995 to 2002.
When Charlie is about to kill Benny at the club, there are cabinets with numbers on it. Charlie is in front of No. 7. Pierce Brosnan played James Bond from 1995 to 2002 whose code name is 007.
In the scene where Charlie is going to the bus station, the driving route has many turns but they are still traveling on St Charles Avenue throughout the scene.
Former Bond, Brosnan follows Daniel Craig in the Knives Out series in adopting a Southern accent to play an American role.