It's important to keep in mind the context about which we're speaking. Krauss is an astrophysicist. He's referring to nothing as the "cosmic soup" of virtual particles from which a big bang event could occur. In fact it may be the case that his version of nothing is the only type that can exist at all. That would mean absent all of the "stuff" that we know makes up a universe, a big bang would be inevitable. The implication that Krauss shows, is that a universe can come from nothing, no creator necessary.
Thanks for sharing those links. I did watch the shorter of the two videos. This podcast (audio/transcript) where William Lane Craig responded to Lawrence Krause's arguments underscores the importance of how words are being used. I think Craig does a good job of explaining how that Krause's "nothing" from which he alleges the universe came into being is not actually nothing:
"He ignores the philosophical distinctions between something and nothing, and says science is going to define these terms; it's going to tell us what nothing is. And what he winds up doing is not using the word nothing as a term of universal negation to mean not anything, he just uses the word nothing as a label for different physical states of affairs, like the quantum vacuum, which is empty space filled with vacuum energy, which is clearly not nothing as any philosopher would tell you. It is something. It has properties. It is a physical reality. ...So when he says there's not a great deal of difference between something and nothing it's very evident that he's not talking about nothing in the sense of universal negation – not anything. He means the quantum vacuum or a state of affairs, a physical state of affairs, where classical space and time don't exist."
https://www.reasonablefaith.org/media/reasonable-faith-podcast/a-universe-from-nothing