Since it’s debut in Forza Motorsport 4, the Hennessey Venom GT’s rear active spoiler was not non-functional. Instead the spoiler was in it’s up position by default and the down position was implemented as a Remove Wing option.
Need for Speed Rivals, which released the same year as Motorsport 5 featured the Venom GT in its car roster and unlike Forza’s model has a functional active rear wing.