The Boers were mainly Mauser customers and real Mauser fans as well. They would have preferred the Mausers first as a result, many Mauser rifles and C96 pistols ended up there.
It's not impossible, but in my eyes very unlikely that DWM made lugers were used there.
A postcard sent from South Africa during the Boer Wars:
And a card that was for sale a while ago:
