It's just that saying "I don't know" when your uncertainty is less than 0.000000000000000000000...(many more zeroes)...001 is kinda specious, just because it's isn't actually EQUAL to zero. So many of us have stopped saying we don't know, and admit the absobloodylutely overwhelming evidence for natural causes with no divine intervention as sufficient evidence.
In most rigorous sciences, you're allowed to think you know when your uncertainty falls below 0.05! We allow so much, much more than that.