How to drive misc vehicles in the Bonus Game?

I probably might be wrong on this question, but is there a way to use the other vehicles (secret, unplayable, civilian and deleted) in the Bonus Game, the same way as in the main adventure? The CPU opponents in the Bonus Game can sometimes be seen driving them...but why not the player too? It seems only the main 42 vehicles from phonebooths are usable in this minigame.

Only way of driving those in the bonus game is by adding them to the phonebooth & the frontend page for the bonus game via modding or the little harder way by using cheat engine

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Hmm... Well I would of liked to go for Cheat Engine, but... I downloaded it and tried installing it or similar, and a virus warning came up. Though I continued after that, it wouldn't let me install and/or use the tool for some reason. :/

I'm pretty sure Cheat Engine itself is not a harmful virus and the only reason it gets detected is because it has to inject other programs in other to work, which may cause the antivirus to say "Hey suspicious activity is going on here, this program (cheat engine) is injecting this other program to temper with it".
If you're skeptical about it however, you could use a virtual machine!