You're going down the same road I did that eventually lead to me leaving Jehovah's Witnesses.
It sounds like evidence or facts don't matter if they conflict with the teachings of the Bible, especially with Jehovah's Witnesses.
Your mother is using circular thinking to negate your argument.
My favorite argument has always been that Superman is real because Action Comics tells us so. That is no different than stating that anything from the Bible is true if it is only found to be in the Bible.