How to find out the demon's name?

[Spitz the Sheikah]

I've found a few other posts that asked this question but none of them were very helpful. I killed everything on bloodmoon island, I found and read the archivist's journal, and yet I'm no closer to finding out Lohse's demon's name. Once I read the journal, I'm supposed to be able to communicate with the spirit tree? Or I bless it first? I've blessed it, I've tried clicking on it, I can't, there's no reaction. Do I have to enter the vaults below the angel statues? I don't know how to open them.

[Yojo0o]

Did you use Spirit Vision to speak directly with the spirit of the tree? It otherwise cannot be interacted with.

[Chaoslink]

There's a vault you can find by digging a secret dirt pile on the map. Inside is the clue you need to get it to talk.

[Spitz the Sheikah]

Originally posted by Yojo0o:

Did you use Spirit Vision to speak directly with the spirit of the tree? It otherwise cannot be interacted with.

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