Spoke to CX and they said no way. I've found an alternative solution - SZX to KUL direct using AirAsia, and actually $3k cheaper. I told the CX woman if she wanted to keep the business they can give me a call back today, otherwise I'll probably cancel it later on. Would much prefer to use OW, but if they're going to cause so much hassle I don't think I have much choice than to go with AirAsia.