"An uncaused, undesigned emergence of the universe from nothing violates no principle of physics."
False, there are no principles of physics operating anyways, in the first place, there are no principles at all operating or any principle at all can be operating. You are extending and making believe that the universe is a subset of another universe having the same physical laws of ours, but that is not case (could be though, as anything goes but you can never discover it (but you could by simply assigning any truth as in the mechanisms used in Free Physics).
You are extending the laws of physics beyond the big bang, something which you cannot do "logically", since the laws of physics start operating after the big bang. So what laws operate before the big bang ? No laws, any laws, whatever: there is no constraint on the conservation of energy before the big bang, there is no constraint on what nothing or something is, there is no constraint whatsoever on any possible idea, design or theory you want to invent since we are already outside of the "laws of physics", outside of "this universe", outside of anything that has anything to do with us, end of story.
So what is there left to explain when you are outside of any reference system or system of laws and constraints limiting what is possible and what constitutes an explanation ? Nothing is left to be explained since it isn't tied into anything, saying poof it just happened is perfectly equivalent to saying GOD did it or to saying we come from another universe, to saying anything as wild as you want to since it can't be compared, measured and confronted with anything related to us, with anything at all, we are effectively in the realm of Free Physics here Big Time.
Science proceeds by discerning Repetitive Patterns, repeating laws and events, etc. so the enitre idea of "explaining the universe" is already completely outside of science, it happened only once from what we can observe and see, something that happens only once (if there is even an "it" there anyways and if we can even say or conceive of the "origin and start of the universe" (I have my doubts)) is outside of any scientific explanantion by definition, structurally.
And this is the exact same problem we encounter when trying to explain how the first living cell evolved from a soup of chemicals, "the origin of life" and even the origin of any species and up to man: it happened only once, there is only one example, there is no repetitive pattern for the entire process or even for the very first process creating the very first living cell, so this too is completely outside of science: albeit a little less than the "origin of the universe", but the problems encountered are very similar, we don't and probably can never know all of the steps leading to the first living cell, all of the quirk steps and chemical reactions leading up to the first functioning living cell, we only have some bits and pieces, can only imagine some possible paths here and there, it is a very long way off until we can see the entire process if ever.
Posted just now by IronMan79