Sliver-
Your second notion is correct. Phylonurists don't automatically talk to every animal. Read the writeup. In the case of one mark, animals don't necessarily trust them. The witches are only BEGINNING to learn to speak to creatures via Nura. And with only one mark, the plants and animals tolerate the witch regardless of biome. They will not attack. They see you as a friend and will defend if you control a biome they dwell within. But.. .that doesn't mean they will TALK to you. You have to earn that right in some cases. And if you are out of your biome... say your a Grassland Witch standing in the Fringe Forest, forget it. No one's probably going to say a word to you regardless of who you touch. Nura isn't all knowing all seeing and yet I'm seeing some Phylonurists, especially up in Kalea, play it that way.
The singularly marked individual is granted the language of Nura and begins to learn to communicate with plants and animals of all sorts. Nura can even cause the witch to actively associate with insects which are vital forms of life in Caiyha's domain. The witch is granted one biome to look after, and is given often multiple years to hone her skills and branch out to invest time and energy in the space she or he protects. The more skills a witch learns and perfects, the more likely she will feel the urge to move and and resettle, especially when her current biome has been in balance for a significantly long period of time. Many witches at this stage can also 'lose' their marks if Caiyha finds them lacking in motivation or determination when it comes to being her guardians of the world.
So that means that Nura (not Mura):
Nura is the language of Phylonurists. The knowledge of how to completely speak this language is granted to a witch with her first mark. Nura works almost like a combination between empathy and intuition. A witch must make eye-contact with a creature or touch it (if eyeless) to speak Nura to it. Nura is a silent language of emotions and intentions, often conducted like a telepathy that instead reveals images and feelings to each user. Plants as well as animals can utilize this language.
Okay, so a little witch with a mark one... knows Nura completely once marked.. but the application of it, how to get animals to trust her.. how to get grass to talk to her... is completely and utterly up to her and her learning curve. If he or she rp's being awesome at it, then you know... that's no better than a beginning bowman picking up a bow and shooting a shit ton of zith out of the sky dead. Cheesy.
While not being a language EVERYONE knows, it is the ability Caiyha gives to the Phylonurists to be able to communicate to plants and animals. Its not like the animals TALK TO EACH OTHER with it. They don't. They don't automatically speak it. The just magically understand the witch when she speaks it (using telepathy/empathy). But again, they don't have to answer and they don't have to listen.
So that means a kelvic will just come across as an unfriendly or not too sympathetic. And the odds are that kelvic, if you think about it, won't be in its own original biome anyhow. Why should they trust her? They aren't a plant or animal. They are a sentient creature.
Get it?