So, to make the Ghutine Vine more scary, like you suggested, I decided to add some more attributes. The type of fear I am aiming for with the Ghutine Vine is a rollercoaster type of fear; it doesn't look that intimidating from a distance, but once you get on, you doubt if you would survive it, and become scared.
An idea I have for the Vine is the ability to make any metal that comes near it instantly begin rusting, which I am basing on the "metallic" attribute of Ghutine. This could be harmful to flashlights, sensors, weapons, or other metal things that could assist you exploring the chamber. This means that exploration will have to be done using non-metal things like lanterns and torches, which are far less effective than their metal counterparts.
Another idea I have is that the Ghutine Vine by default is in a "dormant" state when there is no life to kill, just slowly growing like a normal plant. To put it in an "active" state where it tries to eat you, you have to put force on the stigma of one of the flowers. This sounds easy to avoid, as all you have to do is not step on a flower, but since it is so dark in the chamber, and as I said, flashlights instantly rust, you never know where your next step would end up.
In the active state, all the things I said would happen, happens; flowers start shooting their spores, fruits will become sticky, the Vine would begin growing ludicrously faster, and its vines would reach out to grab you. Once the Ghutine Vine has grabbed you, it would begin pulling you down to the deepest part of the chamber, where the roots of the Vine are. It would pull you to its mouth, and eat you.
Also down in the deepest part of the chamber, is the Ghutine Tribe's MC-Edit tool that carved out the chamber. It hasn't done anything since but lie down in the chamber, but since it is so powerful, it is very risky having it down there.
So, the type of fear I ended up with wasn't a rollercoaster type of fear, but more of a low-risk high-consequence type of fear, which I am happy with nonetheless.