Captain Holt's Twitter handle "@5261796d6e6420486f6c74" does translate to "Raymond Holt" in hexadecimal code.
When Jake and Charles enter the apartment Adrian is sitting in there and says "what's up, jerks?" This is what Jason Mantzoukas (Adrian) screams each time he is introduced at live shows for his podcast "How Did This Get Made".
Pimento says that Kevin Costner's British accent in Robin Hood: Prince of Thieves was very good. It was a terrible accent. There was a parody Robin Hood Men in Tights in which Carey Elwes says that he can speak in a British accent.
In addition to the Vulture's mud wrestling event, Jake and Amy's wedding is taking place the same day as a Lady Gaga concert.
Jake mentions saving money by buying the movie John Wick (2014) instead of renting it every couple of nights. Jason Mantzoukas (Pimento) later appears in John Wick: Chapter 3 - Parabellum (2019) as one of the Bowery King's assassins.