It looks like the lighting issue is either still a thing with Blood of Ancients, or it recently became a thing with today's patch (I wouldn't know, since I haven't played this stage since before the patch that fixed the lighting for The Power Source/Secret of the Ancients/Sphere of Influence).
I've played Sphere of Influence to troubleshoot, and I see no observable problems.
I just realized I've still yet to finish The Power Source, so I'll update this post when I get through with it.
*Update:
The Power Source/Secrets of the Ancients, the final 2 missions of the New Romulus Aid arc, are showing no problems with the lighting.
Comments
At the time, I actually reported the bug for all three missions, but since Source and Sphere were more prominently encountered with people playing those missions, they were fixed.
"Blood of Ancients" wasn't fixed at the same time and remains unfixed!