Reward flights don't attract Avios, but as you've spotted they've effectively upgraded your fare class, so who knows? You may get some, but really you should not.

In theory the JNB leg is upgradeable, but given your ticketing history I suspect it will fall into that well worn category "too complicated to sort out". Personally I wouldn't even try it, and maybe focus your energy on getting an Upper Deck seat in CW. You may get an Operational Upgrade anyway. Your EZE leg looks to be in First anyway to me - or is there a typo there? C and D are CW but F is First.