I agree with Hawking's stance on philosophy vs science, and proximate mechanisms are just temporary place holders for the inevitable distal mechanism that everyone seems to ignore. To put it plainly, an uncaused cause is required to believe in creation. Eventually that's where you end up, and it's a paradox and a double standard.
You cannot test "creation" as it infers, by necessity "creator".
That "outside the system" is just another system. It's like saying a fish aquarium is a system and my living room is outside of it, and that because the fish exist in an aquarium, someone must have put them there. But you cannot stop there and call it done. Who put them there and who put that person there to do that?
Basically you're just moving the problem to another dimension to dismiss it with the wave on the ontological hand.
This part I agree with, with the caveat that there's no empirical evidence for creation in the cosmological argument arena. There's no precedence to use to even know what to consider as evidence if it did exist. We can posit a large number of things and call them possibilities but not know whether or not they are actually possible. For some reason many people seem to consider ignorance a sign of a possibility, as if not knowing increases odds or reality.
Not for you, but just as an example:
My keys are in my pants pocket. If I didn't know that, and I started looking for my keys, what's the possibility that my keys are anywhere other than in my pants pocket? Zero... but people don't seem to move that way. They instead remain ignorant and consider that "keeping my options open".