I wouldn't have either until I saw it growing in Loren Russell's bog some years ago. I still didn't really believe him but I had lots in pots for I could afford to lose a few experimenting. So that fall I put some bulbs in my carnivorous plant bog. I actually just nestled them into the living spaghnum moss on top. I figured they were likely gonners. Nope, next spring they popped up and bloomed. I still wasn't convince since the winter had been mild.
Well, this is now their third year in the bog and they're up again. Last winter was the true acid test of hardiness in my Zone 8 garden. It got down to around 13 F in November and we had another cold snap in December or January. No snow cover so these babies were cold. They seem to be multiplying too. Except for the two weeks of cold we usually get each winter our winters are rain drenched-40-50 inches between about November to at least April.
So once again the moral of the story is "Plants don't read books". Obviously Rhodohypoxis don't require a dry winter although they may require good air circulation.