I first thought someone had sprayed it with lens cleaner then never cleaned it all off. But it's inside the lens. Either on the back of the front element or the next lens in.
That's a pretty crappy turn of events there. Oh well, there's others, right? Schrodinger's lens: it both has fungus and does not have fungus until opened.
Oh well, it's boxed up, labeled and tracking number created. It starts it's return trip tomorrow.
And I'll bet dollars to doughnuts the seller will say, "I don't see no fungus!" To which I'll send him the photo, "So what's all these spots that look like the Andromeda galaxy?"