Same problem, to my understanding, as "outside" requires space to be meaningful.Sorry:
Yet time clearly came into existence 13.8 billion years ago. Space too. 'Before' the BB there was no when and no where. A state in fact of nothingness? Or at least outside of nature?
I'm not hair-splitting here, though this kind of discussion often descends to that level. To me, arguments like the kalaam are not debunked by the conditions of the big bang, but rather not applicable at all. With no before or outside, there is no meaningful way to refer to a cause for the big bang.