I think your reading into this to deeply, this is where you need to create a happy medium between on-road and off road, far as I'm concerned it doesn't really matter what sort of vehicle is required for this run!
This is where you need to think outside the box and decide on a vehicle that will suit both surfaces, so if you want to build a full blown Baja rig, WRC rally car or just a plain Jane 4X4 or even a standard car then go for it and have fun, that's what this is all about mate!
Yes the route is not that demanding, it's not DAKAR where there's no route at all and you rely on GPS