I am going to say I am not qualified to make the determination. I don't work with the gene, and from the pictures I have seen they look pretty much the same to me until a super or als is produced. That said when I started I couldn't tell a phantom from a mojave now they are night and day, so these guys could be seeing things that I cannot yet.
I primarily work with BEL complex, enchi and lavender. This is my first year doing YB complex. Next will be my first with fire. So I am willing to play the the guessing game, but I cannot give you a definitive on anything other than what I work with and sometimes even those make me wonder with certain combos. I have a few "mystery" snakes myself.
I would guess that they are right, vanilla because the vanilla super is not white and the fire is so i am assuming that vanilla is going to be darker than fire. But... I am not sure how much the leopard darkened things up.