When Jake is riding in the shopping cart, they pass a subway entrance marked York St (F train). While York St is a real subway station on the F line, it does not have a traditional street staircase entrance. The real station is in Dumbo, Brooklyn and the exit comes out of a building.
Captain Holt wears his Commendation breast bar above his World Trade Center Breast Bar. When the WTC bar is worn, it is worn above all other medals, but below the American Flag bar.
Holt wears his watch with the face on the inside of his wrist, but when "Fingers" places the replica on Holt's wrist, it is with the face pointing outwards. Surely Holt would have suspected something was amiss when his watch, the subject of the bet, suddenly swapped positions like that.
When Jake finds out Fingers stole Holts watch and he says they have two hours to find him before the bet ends. However they say the time is about 7:30 and the bet is that Jake can steal the watch by midnight.
When Holt is explaining how he pulled off his win, Terry is shown dressed as a gladiator and kidnapping Charles at the same time he was at the precinct, in his normal work clothes, talking to Gina in the break room.
Holt recalls that, on the first Halloween bet, the stakes were that he would do all of Jake's paperwork for a week if Jake could steal his medal of valor. In Halloween (2013), the bet was that Holt would do Jake's paperwork for Halloween night, not a whole week.