The laws themselves are not physical, we cannot touch them (hence metaphysical); they govern how matter behaves in the universe.
"A fundamental rule of nature that cannot be broken." Yes, thank you. So, that is my question. How did that come to be from "nothingness"; from un-directed, purely materialistic, and natural processes which supposedly brought our universe into existence?
Isn't a "process" also something that we cannot touch, and therefore "metaphysical"?
The gist of it: if there is "something" - even undirected, purely materialistic and natural processes - it has to be and behave in "some way". You cannot have one without the other.
Thus
my question (the one I asked in the post you quoted and didn't answer
): "what was the sum of angles in a plane triangle
before that rule existed?"
Or to generalize: how did anything behave before it was commanded how to behave?
If you consider this question, and recognize that its premise is nonsensical, you will start to understand our position.
What you can of course ask is the question for the origin of anything - how did that come to be from "nothingness"? (which is something different from un-directed, purely materialistic, and natural processes).
My general answer: I don't know.
A more special answer: I think that the concept of "nothingness" is inherently flawed and self-contradicting. Something didn't come from "nothingness"... something came from something that is completely different from everything we know.