Question about the paladins(unrelated to any other I guess)

[Optimystik]

Yes, we DO know that for sure. Lightning bolt, fire ball, control weather magic missile, quickened spell empowered spell maximize spell, cure X wounds, endure elements etc are all core spells. The vast majority of oots is core material.

Vast majority != 100%.

The fact that core spells are used does not preclude non-core material. The mere existence one non-core spell means SpC is possible until the Giant specifically states otherwise.