Maybe it's more like, the Ficus fruits, since the fruit and the flower are kinda the same thing with Ficus (see Wikipedia). Either way, I guess.
Sadly, I won't be able to watch this fruit develop, because when I asked a co-worker to confirm whether it was an actual fig or some kind of weird growth, he did so by pulling the fruit off the tree, cutting it open, and then throwing it away before I could protest or even get a photo. (He also was under the impression, or seemed to be, that the wasps which pollinate Ficus somehow spontaneously generate themselves in the fruit, because he said there should be a wasp in the fruit he sliced open. The wasps are actually a very specialized species which aren't found in North America -- or if they've been introduced, they're still not in Iowa -- so there's no reason why there should have been.) There are two more fruits forming on the same branch, which I'm just not going to show to him; we'll see if maybe that protects them from the knife-happy co-worker.
(Full profile on Ficus maclellandii here.)