The author might not be malicious, but from going through some of the audio packs, they're really not quality-checking PRs. For instance, sc_medic/sounds/WhereDoesItHurt.mp3 sounds like two-and-a-half sounds stuck together ("Critical? You Rang? Please state the nat--", it cuts off right there, and doesn't include the phrase "Where does it hurt?").
I wouldn't use this repo outside of some kind of sandbox.
Plus, the fact that audio/video assets can have RCE zero days quite often on some of these systems should make someone immediately suspicious. It isn't hard to generate those assets on your own in a way you are comfortable with. I would never, ever, ever install this without forking my own assets and doing my own install, but not everyone is me.
I wouldn't use this repo outside of some kind of sandbox.