The answer takes:
1. South polar centered flat earth AKA PHEW FE.
2. On northern hemiplane, the (extremely high) north star and surrounding stars are reflected by the 1st dome to the 2nd dome to the inhabitants eyes. The actual position is at the celestial south pole.
Where are these supposed "domes," How are they configured, how do you know they exist, and how would they answer my question or explain more and more of the night sky sliding below the horizon as one moves south? And I have no idea what or who a Phew is, sorry.
With respect to previous research and evidences, I conclude that north star and surrounding stars as reflections seen by northern hemiplane people is a MUST, unavoidable model.
If the north is not a pole, but a rim, and people -with different longitudes and different 'norths'- see north star as a stand still star, the paths look CCW, so.. they must be reflections, not real.
However, I still do my research for this model to figure out the details.
It's like the case of Universal Acceleration (UA). This concept was not so perfect in the beginning, especially in responding sharp critiques such as different weights in different places. But in the long run after figuring out new findings, e.g. the breathing earth, UA became very firm as a concept, even the future paradigm in physics.