For anyone having the same issue (Though possibly quite rare), as expected, it’s a problem that UE5 has rendering Nanite meshes. The UE5 engine can’t render the same Nanite mesh twice, meaning Nanite is un-usable for Split Screen or Virtual Reality.
In short - The solution is to just not use nanite meshes at all when making games in Split Screen or Virtual Reality (VR) and possibly anything else that uses two renders of the same scene.