I don't think the distinction is important to what I was saying. The point is that within boundaries of the Topos, the Gods are blind to meaning. It leads me to believe that souls within topoi are difficult to see, the deeper the topos the harder they are to see/comprehend/etc. But regardless, part of the confusion may be how we use the word "see" to be not always literal - sometimes used in place of a more complex description like "sensing metaphysical significance".
Back to the topic, another possible explanation I find less interesting, which is that the gods have trouble "Seeing"/"sensing" through rock. I dislike the idea, but Golgotterath is probably one of the physically deepest places in Earwa (lets ignore the fact that they are in the horn above ground), next to our other big topoi like Cil' Aujas (sp) and The Holy Deep.
The potential effect of topos interacting with gods is more interesting than deep caverns - to me. This allows for further speculation an topos not located underground (Mengedda) and the weirdness of Anarcane ground (and why the NG avoided it).
Topoi and Anarcane Ground seem like opposite ends of a function. If Erwa's existence is somehow observed or described as a wave function, Anarcane would be a peak, Topos a valley, and the rest being some continuum of objective/subjective space. The Gods would see "all of time" in the middile section, with the peaks/troughs being outside the band of their visibility. TNG creates a moving 'blind spot'.