If it turns out that the Big Bang Theory was wrong, and something existed before that alleged event, it would change our Scientific understanding of the origin of the Universe.
If proven, Religion would be Irrelevant IMO
Even if the Big Bang Theory is true, it would still take a lot of explaining by Religion to justify their Dogma re: the Origin of Life via 'The World Created in just Seven Days' and the ridiculous story of 'The Garden of Eden' etc.
I believe in a Universal Life-Force, and Intelligent Design, not Religion.