The Investigation Team will find much along their inquiries, and each individually will find information as follows:

Kanji

He will receive varying reports depending on whom he speaks with ( as well as varying reception to plushies! ), but whether people believe that the Mother is Her own entity or that the World Tree might be a literal actual tree, etc, the overall consensus is that Yggdrasil is life, from beginning to end. That it should be wilting now suggests it is leaning towards "end" - and it has done so before, but never so severely. The end is death, and there has never been more unnatural and concentrated death than in the years the Travellers have been here, supposing that maybe it is death that begets "end". Perhaps if they sought "beginning" instead ...

Souji

He will come across much the same findings as Adachi, and by the same messenger too as Odin sends one of his other ravens to help them along. However, where Adachi's findings will lead him to the possibility of looking through the veil, Souji's findings will lead him to the method of doing so! They'll need to work together to find the location and the process to have the whole - but in Souji's learning of the methods, he will also learn of the threats! Anyone wishing to use the obsidian water must let it consume them; that is, they have to submerge themselves in it, and to do so for longer than maybe a few seconds will not only drown them, but scatter their mental and physical beings, such that would be excruciatingly painful and also drive them mad!

If done successfully, however, the consumed will be lifted into a spiritual trance of sorts, wherein they will enter a subconscious level of being on the same frequency as the Norn. The three women, seen only as moving smoke, will speak and can be spoken to - but only briefly, and they will leave when the user is close to death. To linger after their departure is to surely be mad, and so it will be!

Yosuke

Magic is much more emphasised in Vanaheim, and so he will have a great deal to learn from those that favour education over all else! They will teach him that magic is not power, it is essence; it is in the air they breath and the sunlight on their faces and the soil beneath their toes. It is in everything, because that is what Yggdrasil gives to them! The well of magic overflows to grant life, giving essence to existence and creating the magic of life and death. To perform magic is to tap into this concept; that is, if essence is given, magic will be returned. Pour yourself and your will into the world, and and the world will deliver magic. This is the very core of Yggdrasil's existence!