Okay, I think I figured it out. Lady Bug and Sinthea both set the first of the 4 items in the "Drivel wheels GroovyFunkRefs (for spinning)" too high, resulting in their tires either clipping through the holes for the wheels or crashing the game.
Then, I came in and looked at their vehicles' data files. I looked under GroovyFunkRefs and saw 11's, those two bitches sure thought they'd get best spinning if their tires were Up to Eleven right? Well, I changed those 11s into -1's to make them not only match the Hawk and the Eagle, but also to make it extra fair and easier to steer
The Solution: Since numbers over 10 crash the game when used on vehicles without 6 wheels (like the Suppressor), it crashes without reason. My only solution so far would be to change the 11 in the GroovyFunkRefs to -1
I figured this out when I looked at Toshiba's comment:
When I /investigated/ this issue a couple of years ago, I noticed this for both SLED and BUGUTTI:
11,-1,2,1 // Driven wheels GroovyFunkRefs (for spinning) - MUST BE 4 ITEMS
10,9,-1,-1 // Non-driven wheels GroovyFunkRefs (for spinning) - MUST BE 4 ITEMS
The eleven there is wrong, should be -1. In C2 that would make the game crash.
Now in C1 it seems like it is tolerated? I'm not sure, IMO various versions of C1 might handle errors differently.