I accept that it's possible I may have misunderstood your earlier comments, in which case I should reread what you have said. My use of the term 'all possible permutations' is slightly sloppy, but I was hoping the general idea would have been conveyed.

Define the universe to be everything that exists (which is not particularly satisfactory but lets go with it). What it means to exist is highly dependent on physical theory. Is it not? If you talk of contingency then you are restricted by a physical theory with which we must use to interpret what dependencies mean and what it means to say that something exists and what it means to say something could be otherwise. Its kind of stupid for example to imagine a universe identical to ours except for that light does not propagate in waves; such a thing is not physically possible weather it be modally possible or not. So an assertion that its modally possible is irrelevant in determining if physical reality is wholly contingent.

To say physical reality is contingent is to say that it could be otherwise. If the many worlds theory of quantum mechanics holds, for example, then it's meaningless to say the universe could be different. Since physical theory is necessary for understanding contingencies and causalities then it's a fallacy of composition to impose contingency on the entire universe simply on the basis that there are things in the universe that could be otherwise, because basic principles that the cosmological argument rely on are required to be interpreted through physical theory and therefore a priori reasoning cannot get us there. Empiricism is necessary for making any claims about the universe.

How can you divorce physics from existence and causality which are the basic principles in the cosmological argument?