I would also have a ood harsd look at the following:-
Wiese at lock and Coetzee at 8.
My locks for the WC would be Etrzebeth, Snyman, De Jager and Wiese
My Loosies would be the following Du Preez twins, Du Toit, Coetzee and Kolisi. ( Coetzee has played openside flank also).
Srummies- Faf, Reinach and Jantjies
Flyhalfs - Pollard and Willemse.
Centers - De Allende, Kriel and Serfontein, Am
Outside backs - Mapimpi, Nkosi, Dyantyi, DH van der Merwe
Full backs - Le Roux
Please note the WC squad allows for the selection of 13 backline players of which 3 are scrummies, The other players normally selected are 2 Flyhalf, 3 centers and 5 Outside backs.
That puts a question mark over the selection of Am and eliminate Eterhuizen - whose performances in tests and Super- Rugby has been highly questionable and was rarely good and often questionable.
I know there will normally only be three locks in the squad - and I cannot see Erasmus ever leaving out De Jager and Etzebeth. Wiese is making a huge claim on one of the lock positions as he has also played as a loosie. I think the lock picks would be Etzebeth, De Jager, Snyman and Wiese.
They need three hookers as well and chances are those will be Marx and Mbonambi and ????
Then there are 6 props to be picked - probably Malherbe, Koch, Nyakane, Kitshoff, Beast, Schoeman
It is likely that Erasmus will take along Vermeulen and Brits as well.