Johannesburg to Beijing
 

I want to use one of the U.S. airlines frequent flyer mile programs to get the ticket above but only KLM (for about $8,000), South African Airlines and a few others fly the route. Is there a trick to using miles on partner airlines, i.e. NWA won't show the KLM flight?

You can use Kenya Airways from Johanesburg to Hong Kong, but its probably better to use the direct flight on Malaysia Airlines from Johanesburg to Kuala Lumpur with more connections onto Beijing.

Call NWA about the availability, they always have been good with booking long haul Malaysia Airlines awards for me.