Is it a cx flight number but issued by AA or is it an AA flight number? I have had both some times buying the cx flight number from AA is cheaper and I have done so. however if you do it this way my understanding is that aa is acting as a travel agent and selling you a ticket if your flight is the aa code share I have always found this to be more expensive than purchasing the cx H class ticket. but as far as status goes im sure cx will recognize their own emerald members regardless of their ticket type, im sure that this would go for those flying on redemption tickets as well