This is complete misinformation. Among the primary tenets of Orthodox Judiasm are the direct divine revelation of the Law to Moses, the existence of a divine covenant with the Jewish people, the validity of the Torah as the divinely inspired word. The way you keep Shabbat is the study of and meditation on Torah as divine truth. The first of Moses Maimonides' principles of the Jewish faith is the existence of God.
I cannot speak to any of the rest of Shoshana's statements or any of her information about the State of Israel, but her explanation of Orthodoxy is a complete falsehood. As a result I would advise seeking independent verification for her other claims.
Well, I know a couple of atheist Orthodox Jews--they haven't been thrown out of the community. Admittedly, they're Modern Orthodox. (Heck, I've known gay Orthodox Jews too--they're also still in the community, though they're not atheists.)
I asked a very frum friend of mine about this too--frum means, well let's just say she's from a very Orthodox community--and she gave the same opinion. If you're observant, she said, even if you're atheist you'd still be considered Orthodox in her community. It's just that not many people will agree with you and they'll probably be sorry for you!
Now, again, no Orthodox rabbi is going to encourage atheism. However, at least among the Modern Orthodox, you're not going to find many who will turn away a Jew who wants to be observant, atheist or not.
Remember--we agreed, at Sinai, first to do the mitzvot (commandments) and secondly to hear them. Perform the commandments first, then you'll understand them.
Also a standard (Orthodox) rabbinic teaching is that the mitzvot do not require kavanah (with a few arguable exceptions.) That is, fulfilling the commandments doesn't require us to have mindfulness, or to understand them, or even to agree with them. But, again, by doing, we come to understand.
Lastly, I've never known any rabbi, of any branch, to use Maimonides's principles as a litmus test.
So what kind of Orthodox Judaism are you intimately acquainted with? And what has been your personal experience? I'm a Conservative Jew--most of my contact with Orthodox Judaism has been with Modern Orthodox communities (apart from my one really frum friend.) I've also had contact with the Chabad--I don't think they'd turn away any Jew who wanted to be observant either. I mean, their whole schpiel is to reach out to secular Jews. I also have my BA in religious studies.
So, since you took such exception to me, what are your credentials? It may be that you're from an Orthodox Jewish background and have had vastly different experiences than me. I'd love to hear all about it.