The Werner AI is a tribute to German director, writer and actor Werner Herzog (who played The Client in The Mandalorian, a Jon Favreau creation). Ross Marquand voices Werner and gives a reasonable imitation of Herzog's distinctive voice. Evidently, the real Herzog was asked to voice the role, but it was said he politely declined.
This episode pays homage to Die Hard.
In the Sacred Timeline, Justin Hammer was in jail up into the 2020s.
What caused the change: Justin Hammer got out of jail before Age of Ultron
Justin Hammer co-opts the plot of A Christmas Story (1983) as a story of his childhood (before he rightfully gets called out on it). Peter Billingsley, the star of the film, was also not only an executive producer on the original Iron Man (2008) but also played the role of William Ginter Riva (the scientist who gets screamed at by Obadiah Stane), which he reprised in Spider-Man: Far from Home (2019).