And later, this was shown by others to be true. You have the same opportunity, to show astronomers why you're right and they are wrong.

Elsewhere nearby, you asked why hunters would even bother tracking precession.

See Napta Playa, which dates to 11kbc . The site seems to infer a much earlier interest in precession, imo, just as the cave art, ca30-40kbc demonstrates much skill and sophistication. (Few nowadays could make such art, I would think)

A makeshift observatory. No need to involve temples, the Sumerians, etc.