No one is claiming to know what happened prior to the Big Bang. Whatever existed before time had to be infinite. If you read my logic carefully, I believe I make a perfectly reasonable case for 1. the universe existing (which I think most people would agree, we are living in an existence) and 2. that existence having a start (e.g. the universe is expanding, light gets redder the longer it travels, etc) 3. Anything that comes into existence has a cause.

I think when you combine the scientific evidence with the logic and continue down that line, you can make a good faith argument for an intelligent creator.