Started watching mid movie so please help me answer this question

In the scene where George and Cheryl have climbed out onto the roof of the cinema, a guy with 1/2 a face tries to push George down the hole until Cheryl attacks the guy with 1/2 a face and saves George.

Who was that guy with 1/2 a face? The other 1/2 of his face looked metallic as if he was a cyborg or something. He certainly didn't look like the rest of the demons.

[I also was wondering: George got scratched on his arm by a demon when he was riding the bike in the theater to save Cheryl and even with that scratch, George didn't turn into a demon at the film's end like Cheryl did. But someone on this board explained that: The demon hit George with a chain or some kind of weapon, he didn't scratch George.]