Pretty much what I had to do. Finally they stopped getting trapped in the side street and managed to do enough damage. That one really needs reworked.just using save & load trick. reload everytime u failed, maybe around 5-8 times i beat the gang leader with this trick LOL
dont forget turn off auto save function
What's hilarious is, if you're trying to fail on purpose to unlock the CG, the other 3 (sans Miki, but even hers isn't bad) are laughably hard to fail, to the point you have to minimize movement so they don't accidentally touch a bumper and wipe out every enemy on screen.