You're inadvertently making the odds way worse for yourself by not including Hong Kong as a destination or origin.

I'm sure you have good reasons for wanting the itineraries you do, but Cathay Pacific is a Hong Kong-based carrier. Your searches listed above, by not wanting to actually go to Hong Kong in any of them are doing some combination of requiring partner inventory and/or getting up to 6 sectors (your MIA itinerary if it includes CX metal) instead of 2 per itinerary. The odds (1 in X) literally compound against you.

The cold reality is, if you don't have any status on CX, mileage tickets are hard enough to come by for one sector on CX metal. You're now looking for connecting flights, possibly multiple connecting flights (whereby points tickets must be available for each sector at the same time) and/or partner tickets (which are notoriously hard) in combination. Btw, There is a concurrent thread in here about JAL either having cutoff CX Asia Miles from awards, or making it extremely hard for us to book on JAL. That's what you're up against.

Best odds of using your miles by far on CX are to or from HKG, single sectors at a time!