At the end, after Camille tells Logan she won't talk to him for one week, Logan is not wearing a jacket, but when they go to dance, Logan has a black jacket on.
Bach's Brandenburg Concerto #3 can be heard playing in the background at Gustave's party. At 8:38 a classical bassist can be seen - part of a larger group one can presume - bored and playing nothing. If the music is recorded music, why have classic musicians on hand? It's a wasted expense.
When the 'social gathering' begins and Carlos and James open the door, Jo clearly heads the group; then, as the group goes through, she and Camille arrive at the doorway having FOLLOWED the group.