Oh well, as I expected, the stupid valet denied that they scratched my rim. Demanded a joint review of the CCTV footage and don't know if they will entertain me.
Anyway, guess I'll just suck it up and take the rim for touch up tomorrow. Only HK$350. But really mad. I have no problem paying that but just believe that the one who caused the damage should admit it. I could have forgiven him and not asked him for the compensation.