I think the question on P(God) is a lot more difficult to answer than the surveyors realize. We're all cognizant of the possibility of the known universe being a simulation, a machine constructed by some intelligent entity in a higher level universe*. Some of us consider the probability of the scenario Simulation to be high, if not absolute for reasons I wont go into here.

Many of us are define "natural" as "happened in reality", thus they define "supernatural" as "did not happen". Those may rightfully assign literal 0 to P(God), that is a statement as sure as the axioms of the logic you formulate it in. The rest of us, though, those of us who believe that all words should by virtue of their existence have a use, have to think a bit more. If "Supernatural" means anything, I'd be surprised if anyone here bears a definition that does not render Simulation equivalent to the scenario God as God was defined in the survey.

To me, "Supernatural", if you're going to use it, could only mean "so mysterious as to be beyond being reasoned about or modelled". The work of the simulator's hand would definitely qualify as such, and so too would the simulator itself. Lo, a supernatural creator. God is reality.