1. My claim was that the universe had a beginning and that is what I supported by quoting Vilenkin. Note the spelling.
2. You mentioned a cause but I did not use Vilenkin to show cause. When discussing the cause of the natural world you have moved from science to philosophy. So when I make claims about cause I would use philosophers to back them. Primarily I would use the concept of sufficient causation to identify the likely cause of the universe.
So I use scientists for science and philosophers for philosophy. When your dealing with the cause of nature Vilenkin is no longer relevant.
This is a philosophical issue not a scientific one. Vilenkin is no longer relevant at this point. Vilenkin was trained to examine the natural world not the cause of the natural world.
People do not have enough respect for the concept of ex nihilo. Nothing can't cause anything. As the axiom states "out of nothing, nothing comes". You quoted statements about nothing which used analogy's about things to demonstrate. You should see that Vilenkin is out of his depth. The greatest example of this is Hawking's statement:
"Because there is a law such as gravity, the universe can and will create itself from nothing," he writes. "Spontaneous creation is the reason there is something rather than nothing, why the universe exists, why we exist.
https://www.theguardian.com/science/2010/sep/02/stephen-hawking-big-bang-creator
They need to get back in the lab because they are atrocious philosophers. He basically says that nothing produced everything because something existed. He even made scientific mistakes. He presupposes gravity to explain mass when gravity depends on mass. He ascribes causal powers to natural laws but natural laws are descriptive not prescriptive and can't cause anything. 2 + 2 never created 4 of anything.
I appreciate the honesty. Every claim about the quantum I have heard presupposed the existence of energy fields and so isn't an explanation of those fields themselves. This is a type of the chicken and egg problem.
You seem like a refreshingly reasonable and intelligent person. Would you like to concentrate on the causal argument for the universe alone so we can sufficiently evaluate it?