I believe that all planet creatu that are not bought in the CS shop or found on Uldavi should have the ability to be beaned. Specifically, I am talking about the Viarindi/Feiron/Cetari/Guilbyss. I am not terribly well versed anymore in what else can or cannot be beaned, but I feel that we already have enough pets (like all the cash shop pets and the Uldavi pets) that cannot be beaned.
My main reasoning is that I don't see why they couldn't be. They aren't special like cash point pets, still considered normal planet pets... I don't know if there is a functional reason I'm missing that they shouldn't be, but considering the dye kit market is already inflated like 300% since I was last looking at them, we should be able to find a way to get colors of these creatu that are already hard enough to obtain.
Also making a note that the FAQ page even states "Natural Colored Jelly Beans cannot be used on Credit Shop pets or Uldavian pets" so all planet pets should in theory be included, or else it seems a bit misleading.
Also making another suggestion that it is included on the creatu species page if something can or cannot be beaned.