Why do we know AAK was controlled? It's stated in the issue. On the other hand, while Mr America is prominent, the Kid is conspicuously missing from the next 3 months of covers. So, the team may be wrong about that...or the Kid might not survive his vindication. Or, it might just be a coincidence. Why do we know KC is in All-Stars? Sturges has already revealed the lineup. (And he's on next month's JSA cover along with the rest of the team.)
That article, BTW, makes me a little less annoyed at the lineup of the All-Stars team... I'm still not sold, but I'm willing to believe that the next couple issues of JSA and the first couple of JSAAS will sell it.