Hi TrapperJohn:
It's not a "flaw" in the lens, and it has nothing to do with CA. It has to do with reflections off internal surfaces in the lens. It is red, or reddish, because that is what results from the reflections off the sensor plus glass elements.
If you look at your original shot you will see the ghosting (we call it) actually covers the tree trunk in the left foreground; this could not occur from light going through the tree from the sky!
It is difficult to design this sort of lens (the way they have) without the associated back-reflections. I would also be a bit surprised if they actually did the ray-traces necessary to show up ghosts from exposures as long as you made them with a sources as bright as the Moon, and almost in the centre of the FOV.
IF they (the Olympus designers) had thought people might use this lens this way they could have used more specialized coatings on their glass elements, which would have boosted the cost of manufacture even more. The trick for the designers (in their next version) would be to force the majority of the ghosting light to the region outside the FOV. But anybody doing serious wide-angle astrophotography is not going to be doing it when the Moon is up, and is that bright.
I hope this helps explain the ghosting you've detected. You'd be waisting your time trying to convince us that it actually is a secondary near-IR halo.
X.
