The universe whatever that may be is a game of energy in one format or another.I really hope you're not referring to my comments because I don't consider them as answers.
No offense but, this sounds like "accept it or not, that's how it is now and you better don't challenge that"
But then, why disapproving or defending something that was not proved in the first place?
There are few candidate theories you surely know about that could evolve to answer the missing "creational" portion of the BB or even give a complete new theory at some point, candidates listed for:
Theory of everything - Wikipedia
since we see an expanding area with views beyond our vision it had a start point.
Winding the clock back put at least what we see all back to a start location so i would say the big bang is on solid ground as a theory.
What creates the energy and what is the mechanism for a BB is the real subject of what the universe is and how it came to be.
Right now we see an explosion but have no clue how that explosion came to be or how the tnt came to be for the explosion.
IMO the universe is endless fluctuation that is the cause for energy building in regions and reason for BB's when energy levels get to high in one region or BB's collide.
Fluctuation right now creates sub atomic particles then promptly destroys them.
Before fluctuation became balanced it probably created sub atomic particles and didn't destroy them.
That gives us a start point to creating everything and a new perspective on what the true universe might be.
Then the question of what is fluctuation?
If we have an area of endless void space that has nothing it it but consumes space does it have potential energy? That could be what fluctuation is, just a balance of potential energy.
To have any format of a universe we need a deeper understanding than expansion from a 0 point of space for no reason.
That is the current BB theory.
Our BB might simply be 1 expanding BB in forever with endless other BB's in every format possible from giant black hole to compression to expansion and sub BB areas with not enough energy accumulated to do anything yet.