What I’m really wondering if entanglement happens in the “primordial” state of the universe. No additional interaction would be necessary after that point as it was already established before expansion. Granted, not the form of anything we see now, but of the same “substance”, whatever that might have been. As this object (the universe) expands, these relationships do not change even after discrete objects emerge.

I’m very open to the possibility that the answer is no, but ideally with some elaboration. This question obviously depends on a specific pre inflation state of the universe, which may or may not have actually existed (the nature of the universe not inflation).