Well, in the campaign I described it was "the Buddha of the Pure Land in the West" - whatever exactly that means (the paladin in question wasn't very intellectual, and so the metaphysics never really had to be worked out - though the paladin's conception of the Pure Land Buddha was rather different from the esoteric monk who sought to emulate the Five Infinite Buddhas; and also presumably was different from the Emperor of Heaven, who was also a fully enlightened Buddha).I agree - and if the Paladin can do that and still retain his powers, it just means there is a LG power higher than the Pantheon that is granting them, and that approves of his actions. Perhaps that power is the LG Alignment itself as a cosmic force.
But my point still stands - as far as play was concerned, it was the player, not the GM, who determined what was required conduct for a paladin honouring his reverence of the Buddha and his commitment to those values.