That's not how proof works at all. Proof shows that something exists, what would proof of nonexistence look like?
You cannot prove that anything doesn't exist, only things that exist have proof.
If I tell you there is a large purple dragon in my closet and then ask if you have any proof that I don't, you can see the idiocy of such a statement. Your god is just another purple dragon. A figment. I don't need proof that it doesn't exist (as that's nonsense) the extraordinary claim of a magical all powerful yet invisible and undetectable being NEEDS PROOF.
Any one single shred of proof is sufficient to show that something exists.