"They play soccer, even though they are ill."
Translation:Sie spielen Fußball, obwohl sie krank sind.
My guess is, they just forgot it.
But theres a slight difference between obwohl and auch wenn (even when nowadays many people dont care and mix them).
", obwohl sie krank sind." This is a statement. They are ill and they play football and the illness does not stop them from doing so.
", auch wenn sie krank sind." This is somehow a condition. It does not describe they are ill now (or at least its not necessary that this is true), but it describes that being ill will not stop them from playing football. So if they play football, it does not matter in any case if they are ill, they would still play.
Most of the time both things can be exchanged, because often one or the other expresses eachother AND very many germans mix them too without caring for the subtle difference. If youre writing a text for your university in any social science field, then stuff like this matters (or when you write for a reputable newspaper).
After the long text. I dont know if the english sentence can describe both since its already "just a small detail" in german.