Actually, FFRF has hundreds of members -- and one employee -- in Oklahoma!

4/ Late -- The Buddha knows all the metaphysical answers and doesn't mind pronouncing on them. Indeed, by the Abhidhamma it's almost all that's discussed. I think these trajectories trace the changing rhetorical needs of the Sangha as it struggled to survive against Brahmanism.

3/ My view is that we can trace "trajectories" though the Pali Canon, that roughly look like this:
Early -- The Buddha rejects metaphysical speculation.
Middle -- The Buddha knows all these metaphysical answers, but refuses to teach anything but suffering and the end of suffering.

2/ The sutta itself portrays Gotama's enlightenment experience as one in which he sees everything and learns everything. Most of this is in the metaphysical rather than the phenomenological realm. This material is undeniably in the canon.

I ran and refreshed my memory on MN 100. So many things to say:
1) The sutta is obviously quite late. The widow's offense -- the one that gives rise to the whole narrative -- is to repeat "Namo tassa bhagavato arahato sammasambuddhasa" three times!

If by "unseen" James meant "imperceptible," I think earliest Buddhism would still resist definition as a religion. Remember one of the characteristics of the Buddha's dhamma: "Ehipassiko."

My view is not quite that earliest Buddhism was atheistic. Rather, Gotama had no use for metaphysics at all. It seems he saw speculation beyond the phenomenological realm as a hazardous waste of time. So a Buddhist is not compelled to accept supernaturalist ideas, and I don't.

Yes! Introduce them to the guy who's holding that gun to their head! They should at least know the name of the one who's threatening them with eternal agony?

I think so.