Why Is Fred Driving The Digger?

This picture is called this because, not only have I been in contact with JMMB on the last picture, but I want to be able to race in RR's car and have an opponent in Adventure Mode race with RR's car too. I thought about changing the Digger to RR's car to do this. But for some reason, Fred is driving his digger instead of RR's car. I'm confused because this is the opposite of what JMMB said:

"I found that changing the digger's .CCD pointer to Rocket Racer's .C[C]D file will replace your opponent's car to RR's (in the race, not in the construction site on Sandy Bay), but not the inverse for any of the cars you would race. "