Hi! I really love these assets and intend to use them in a game of mine. Are these available to use commercially? (With credit!) And is there access to the files without the generator itself?

You can use them commercially.  After you generate the files they should go to your AppData folder on your C drive  C:\Users\*UserName*\AppData\LocalLow\RyanSPeterson\Altercation\Export

Good to hear but is there any chance for the raw image files? As I'd want to adapt it into my character creator and exporting individual portraits wouldn't really work.