I have the impression Cathay is going an independent route within Oneworld.
Of course they have some Codeshares, FF deals and Logo's spread across the process ..
However I don't see HKG developing into a hub for other airlines then CX. BA does everything via SIN (& competes with CX on Australia !!)..
Cooperation seems opportunistic, Cathay perhaps feels / knows it can do very well by itself doing a one stop operation Asia-europe and Asia-North America via their new HKG Hub ....
Does Cathay need Oneworld to be happy ?