it will originate at the exact location of the brow chakra and then project out at a 45 degree angle because the pineal gland houses the third eye it stores up on light energy
I am not a know it all but I do have some years of experience in meditation and astral projection and I teach kundalini yoga. So what I am telling you can be verified in old yoga books like Yoga Sutras and Bhagavad Gita.
My experience is that pineal gland is related to third eye and work in conjunction with it but it is not the third eye , nor is it the exact physical counterpart of third eye. the thing that is the corresponds directly to pineal gland is your imagination faculty. That is also an eye but it functions differently and occurs in the middle of the head and not at the center of the eyebrows.
I am not familiar with the third density terminology so you will have to take their word for it and try to verify it for yourself.
The idea that it can project at 30 degrees is valid.
I have had experiences where a tube protrudes out from the center of the forehead and goes in any direction one desires and even acts as a microscope where it can see into micro-organisms. Third eye is capable of many types of visions, even vision like Imaging machines which are used in medical science, but in yoga our main concern is to see into other dimensions and to travel there.