So, roughly they, the US cat team, need to get above 20th in the future worlds/ocr to get into the top third, and there are 7 more open spots . Also there probably are not 7 better countries so the US is ok assuming the top 1/3 thing is no problem.
It's not that simple. Only three slots are available at the 2015 Worlds. If the US does not get one of those 3 slots, there will be a continental qualifier with one spot.
So, there are only 4 remaining spots available to the US.