That is a good question and while I am no where near being a physist, biologist , chemist or any mix of the 2, I do know a little about the neuro-chemistry of the brain.
IF we can use what happens in brains, be they humans or other animals, we see that not one area of the brain fires off chemicals at a time, but multiple areas. Thus many areas of the brain function at once dumping various chemicals into the brain at a given time after an external stimilus triggers something.
Now IF, and that is a big IF because I’m going on a theory, the universe works anything like an organism’s body (such as human, chimp, cat, dog, mouse, etc), then such an idea of multiple sources involved in the formation of the universe is plausible.
Also, if we observe the earth or even space, there is activity happening everywhere, so it would make sense that a combination of various events at different points and eventually combining would, in theory cause a big bang eventually when they collided to form the unverse.
Now mind you, I’m just pondering your question based on what little science I do know and understand, so only take it as theorectial thought and nothing more.
OY! I just realized something I said about the brain in this line of thought- don’t ask me what the external stimuli would be for the creation of the universe. I couldn’t and would not begin to even go there with a theory. Trust me, I’ve tried as a child and never got anywhere. I just went in circles. :(