We can definitively state that God is outside the purview of science because that's what we define science to mean. Similarly, we define the trade of "plumbing" or "carpentry" in such a way that God is outside the purview of plumbers qua plumbers. Why don't you go yell at some plumbers for not investigating God as the source of clogs and leaks for a change?
Well sure. But who is anyone to know whether we have the competence or objective basis to define science as exclusive of God when science has no competence in the matter to begin with? And for God's sake don't bring my plumber into this. We're dealing with the fundamental assumptions inherent in anyone who undertakes to understand objective reality. This whole issue is not nearly as intrusive to general scientific pursuits as either side cracks it up to be.