This is an important point. We know what our DMN is and how we use language as a basis for thought to create concepts and complex ideas. However language also bounds our thought. What about the Dolphin? It is a fundamental philosophical problem of if advanced intelligence can exist without language. We have a pretty good notion that you need some sort of substrate (language) to create intelligence. And we know that mapping the internal state of a brain from inside of itself is incredibly hard and the way our human brain evolved to do it is really fascinating but also full of hacks and mismatched mappings based on what we know is actually going on.

Cognitive computer science explores this whole area of mapping language and the underlying semantic meaning. Ultimately, these intelligences will be bound by physics (unless some new physics or understanding therein happens). And classical intelligences are still bound by classical physics. So I am not sure we can't relate to these other intelligences. We may be limited to some translation layer that does not fully map, but can we still relate to some other consciousness? For that matter consciousness is just another word that vaguely maps to a vast and extremely complex thing in the human brain and each person has a different understanding of what that is. I don't really have any conclusions, you brought up interesting points. We should sit within this realm of inquiry with a lot of humility IMO.