There are all minor and/or unseen characters that appear in Knight of Gotham.
Vincent Falcone was the father of Carmine Falcone and was the previous patriarch of the Falcone Crime Family, as well as the Kingpin of Gotham before his son rose to power. He passed away several years before Batman first appeared in Gotham City.
Stan was Selina Kyle and Holly Robinson's pimp when the both of them were still working as prostitutes. Stan was also Selina's abusive boyfriend. His only appearance was in the pilot, where he was portrayed by rapper Eminem.
Alan and Mary Wayne
Mr. White (first name unknown) was a mobster who was a member of Carmine Falcone's inner circle. He was in charge of the Roman Empire's finances, serving as an accountant and money launderer. He was later killed by The Reaper, and is succeeded by his son, Warren White, who would go on to become The Great White Shark.