Ral second ability is working differently with cards that store mana based on the status of the card.
If the card have filled the normal cost ral give no mana to the stored mana. If the card still need mana to fill its normal cost, ral give mana to fill it, and the rest left go to the stored mana.
Not sure if this behavior is the intended one, but it should give or not give mana to the stored value always
//Edited Title - Tombstone