Well, it’s not ‘African’, but a hybrid of Afrikaans (ja/yes) and English.
In substance, it’s a very Beckettian phrase. Think Waiting For Godot, set in South Africa; that moment at the end of the play when Vladimir says to Estragon ‘Well, shall we go?’, and he replies ‘Yes, let’s go.’ And neither of them move.
That’s a very ja-well-no-fine moment.