I think Rattling is fine. The point about Rattling (including East Africa) is that there is no 'obvious rufous wing panel' not that the wing has no reddish tints.
In Winding, especially in fresh plumage, there is a wing panel which appears as quite a bright red against a black-grey streaked back - see attached photos of Winding. It used to be called Rufous-winged Cisticola, but this name is now for former southern African C. Galactotes (aka Blackbacked Cisticola), which looks very similar and is what might be found at Kruger (though the maps in the books suggest it may be more coastal and might not get quite into Kruger (I don't know)). These two used to be lumped under C galactotes but were split at some point.
I think it's true that they can look more similar from the side in worn / non-breeding plumage or when wet.
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