If “God” is indistinguishable from the natural world, unable to be differentiated from it, to formulate or express thoughts or to influence existence in any way, it is a redundant idea, a zero to the left, and something so alienated from what the vast majority of people consider God is, that the meaning of the concept has already been twisted. It doesn’t deserve epistemological effort, because our understanding of the world wouldn’t change one bit: rather than it being a wilful intelligence, it would be a carcass over which we happen to live in, which the Universe already is. Even if you were to prove the existence of such a devoid concept, it would be equal to asserting “The Universe exists”.