You're confusing two separate theories, probably deliberately, possibly in order to forward a pro-religion agenda by the sounds of it.
We "know" the mass of the universe, to a certain extent. We also know that if, after plugging it through lots of equations, we get something less than 1, the universe will collapse and expand forever. If we get EXACTLY 1, it will expand to a fixed size and stop forever. If we get more than 1, it will expand forever and never collapse back. We currently measure that figure to be 1, plus or minus several dozen (i.e. totally inconclusive).
None of that has anything to do with the fact that the mass we *do* see out there (by observation) can't be ALL that's out there because there's hidden stuff "tugging" it about and the only explanation is hidden (dark) matter. We know how much that hidden matter must be (by the extent it tugs space/matter about) so we take it into account with everything we "weigh" in the universe. But this article is about finding out what that dark matter is, not how much it weighs. You're talking about finding out what that number is, which is based on what we KNOW must be out there (we just can't see it), the article's talking about what nature of material some of that hidden mass that we KNOW is out there actually is.
Spuriously related, but entirely separate issues. And not one single jot of it has anything to do with God. It can only be good for us that you left physics all that time ago, because you're mixing two separate things in order to bitch about someone who has more accepted published papers in physics than you'll ever write (or even understand). Whether or not he tried to do it starting from an anti-God assumption, I don't care - his physics was, and still is, pretty sound. But, to be honest, I'd be very surprised if that's how he started off, or if God actually figures in his equations at all and think it's just you mis-interpreting the book and confusing two entirely separate portions of it, again.