Why be masochistic about the thing? Email the Cathay office in CMB to get a price for your ex-JNB ticket; I'd be shocked if they didn't get back to you with a price in 24 hours, and they know the rules as well as anyone. I don't know the politics about picking it up in JNB - there seem to be some people in the office there that need attitude adjustment.

Why does Cathay tolerate this kind of behavior? Probably they have an employment environment that gives them no alternative.