Deep in the bowels of this thread, I had it right (nonstop TG703 BKK JNB early Wednesday 29 June 0115+1 0730+1, but this does not work for early Thursday morning in post #63 on July 1), but thanks for reminding me, Neobie.
That means TG703 works for June 29, with a 27 hour layover near Oliver Tambo airport in Johannesburg until SA170 departs.
The alternative through Singapore and Perth is delineated by both me and by Neobie as long as any BKK SIN flight leaves by 11am. However, the more direct route involving SQ478 0210 0649 works with any BKK SIN flight on June 29 but only the SQ478 on June 30 is a possible conncction.
Addis Ababa works on June 29 with BKK ADD ET609/607 0035 0525 combined with ET763 1036 1631 or ET765 1442 2050.
I find the most interesting connection point NBO. One June 29, KQ887 0055 0625 gets you to Nairobi early enough to connect with KQ722 0825 0935. Why didn't teams take that? It makes no sense to me unless their travel agents did not find that connection or either of those flights was full. There were other options through JNB which took a day longer.
One final connection point is Dubai, which actually had the most options for June 29:
BKK DXB EK385 0125 0430, EK419 0240 0545, MH6142 0435 0830 all of which connect with DXB JNB EK763 1036 1317
BKK DXB EK375 1018 1317 connecting with DXB JNB EK765 1442 2050
My overall conclusion is that commencing no earlier than midnight starting June June 29, except for the one June 29 connection through ADD, all routes led to Johannesburg and connection with SA170 on June 30. There were possible connections through each of the airport listed above.