Hm, I thought that reasoning argued against your own non-serious first paragraph rather than what Bill said. If the idea is "if God is real (and won't let snakes bite me), then they won't bite me", then being bitten shows that the first part is false, but not being bitten doesn't say anything about the first part being true or false.

Or if you don't want to get hung up on formal logic, then it's valid but very weak evidence, like a hypothesis not being falsified in a test.