The reason why the celestial poles are opposite from each other is explained in the video, as are the answers to other questions poised.
No, it is merely asserted in a manner which makes absolutely no sense.
For the FE model, the crepuscular rays are not a result of perspective. They are a result of the sun being near and thus sun rays actually diverging.
This provides no explanation for anti-crepuscular rays.
The only possible explanation for anti-creuscular rays in this context is as I said, the light physically bends and starts converging opposite the sun.
I have also now realised that there are even more issues.
This would only work for one specific location.
If you move closer to the sun you will observe the anti-crepuscular rays to first diverge before starting to converge.
If you move further from the sun you will observe the crepuscular rays to first diverge before starting to converge.
If you move to the side you will observe the rays to diverge from the sun and then converge towards another point, which is not simply in the direction opposite the sun.
The crepuscular and anti-crepuscular rays only make sense in the context of a very distant sun producing effectively parallel beams of light with perspective then producing the apparent convergence/divergence of the rays.
None of that is addressed in the video. Instead it just takes the anti-crepuscular rays as given and working perfectly fine for a FE, even though the refute the common FE model with a close sun.
Likewise there is no justification or explanation for why the stars should be anything like these rays.
Of interest, I notice that when looking at the southern star trails that the outside trails are brighter and thicker, compared to the less vibrant inner stars. It's like we are looking down a tube.
I notice that they are brighter when higher in the sky as they have to pass through less air.
However I also notice that some are naturally less bright than others and some naturally appear thicker than others throughout.