The earliest OOS that shared that they received an II (interview invite) said they got it on 9/16/15. I'm OOS, too.
You mean you got a secondary invite on 7/7? They do screen primaries. Columbia does not screen, but Greenville does.
MSAR says out of 2510 OOS, 134 OOS interviewed, and 33 matriculated. Chances are relatively slim, but no worse than any other OOS school, really.
Don't worry too much. If they like you, they'll contact you. It's a waiting game that sometimes takes a few years to hit.
I graduated with my B. Sci. years ago and it hasn't killed me yet. This is my first hardcore app year, so I'm hoping like you that it doesn't take more than one.