the ticket is valid for 1 year from the date of first segment, and date change is free if routing is the same.

there is no mpm jnb on oneworld.

i dont know how marco polo club point works and i personally think marco polo is not a very good program, especially for done fare.

the base fare for both jnb and mpm in d class is over 6000usd, i believe and one has to pay fuel surchages and tax on top. so easily 7k usd for the ticket which is still a good value if money is no a big problem. probabaly around the same ex japan.