While Kryten speaks of "getting the T-72 from the WW2 game", the tank shown is actually a T-55 with retrofitted explosive reactive armor.
When Kryten re-enters the AR suite to interrupt the Jane Austen game, he says he's looking for a T-72 tank "from the WW2 *game*". The T-72 wasn't in production by the USSR until the early 1970s. The Soviet's main tank of World War 2 was the T-34. However, that fictional game must have been developed at least several hundred years after WW2 and the fictional game developers could easily just have been sloppy or misinformed.
Kochanski states that Hue is the third largest city in Vietnam; Hue is actually the fifth largest. She also mispronounces Hue ("hwah", rather than "hway") despite making a point that it is pronounced differently to how it is spelt.