This was not an idle supposition from Gary Smith because, according to the available information, people survived in this gathering place.
Otherwise, how would this secret realm and these wall painting-like contents could have been passed down?
This ancient Beastmaster might be the survivor from this gathering place, and possibly the only one.
After all, if there were many of them, they would have taken the remaining people to start new settlements and breed, rather than creating a secret realm for the destined ones upon their death.
As for the part of the body of the Divine Incarnation, it is hard to say. After all, the flesh and blood of the high-dimensional beings are the greatest abnormalities, which could even erode the surroundings into a forbidden zone for life.