First off, credit given for writing up an explanation and posting in a public forum, even if I do think this is a crazy take that doesn't stand up to pretty much any level of scrutiny.

And I say christian instead of religious, because she is clearly referencing the idea of a grand plan that is not present in polytheistic religions, she’s talking about god’s plan.

There is a colossal reach from "there is a god with a plan" to specifically Christianity. Judaism and Islam don't get a chance to audition for the part at all, huh? And that's just the Abrahamic traditions that directly share the only attributes you listed. There are plenty of other religions that fit, and that includes other monotheistic belief systems (which also begs the question, why is Christianity not categorized as polytheistic and why does that distinction matter at all?).

I'm also just going to assume you mean evangelical Christianity and not other sects, given the general unawareness of the subtleties of religion in general.