You have several flipped normals on that mesh…
I made sure to get all of them flipped and also used a weld modifier to make sure it was all joined…selecting all interior faces and then deleting…
As far as I can tell everything is fine but checked with a quick node assigned to Backfaces…
Outside…
Looks clean of all interior faces…
Could you share that node setup in a file? I can’t tell if I don’t have some of the nodes or I just can’t find them. 
There are no incorrect normals on my mesh. In fact it’s quite literally impossible for there to be any incorrect normals as this is just a bunch of cubes, all of which had proper normals.
I made it in 3.5 alpha, opened it testwise in 3.4, should work too, 3.22 is too old.
untitled.blend (582.0 KB)
Ah, that’s why. I still haven’t updated Blender from 2.93.
Here’s my best solution to this issue. (Note that this action must be performed before removing duplicate vertices)
