To answer your questions,
No, the bus wires are not twisted, and the two bus wires are pretty much right next to each other.
Regarding the hot snubber, I would have never noticed it except for the fact that I was working on some wiring under the layout and happened to notice it. I wonder how many modelers ever check the snubbers since they are under the layout, out of sight and out of mind.
I cannot help but wonder, why this particular snubber? If "the snubber is doing its job as intended", what is it doing, and how would it be noticed except by chance.
I go back to my original question. Why is this particular snubber hot, and is it anything to be concerned about?
I really appreciate all of the help and attention that this thread has brought on, but I remain mystified as to whether I have a problem and, if I do, how to fix it.