I'd give a different name for atheistic culture, such as secular humanism, neoliberalism, and so on. Scientism is more specific.

The nonbeliever's counterargument would be that if it's just another room in the hospital, anyone could guess what's going on in there based on general knowledge, since all the rooms are similar. There would be doctors and patients doing their thing in each of the rooms.

Plus, there's the question of how the report is recorded. Are only the accurate parts counted, and any inaccurate predictions discounted? Is the revivified person's account ambiguous or open to interpretation? If so, that would introduce a subjective element added by the doctors or the NDE theorists.

Moreover, why would the disembodied spirit travel just to another room in the hospital? Why not to Mars or to another dimension?

Also, there's Occam's razor, and the lack of a supernatural theory that explains all the natural facts plus life after death. How does the disembodied consciousness sense anything without sense organs? Why is its knowledge confined to just the next room, as if it were still bound by space and time? How does the spirit interact with the body (the philosophical problem of substance dualism)?

And was the person fully dead, as in brain dead?

But these questions are off the top of my head. I haven't looked into the NDE reports.