I had envisioned, that she is still near the tree, but we should be about 50 feet from the tree at least (that's where Allyra was going to cast her spell, which, as I understand, has not happened yet, because of the woman suddenly showing up ).
Anyways... close enough for Arcane Sight, which is what I wanted to know in the first place.
I assumed you were coming towards the tree, casting Arcane Sight as you went. Then she popped out from behind the tree. Hence the closeness. But you can be father away if you want.
I'll be on vacation for about two weeks. Don't wait on me, Allyra will just stay in the back and tag along, or whatever else seems reasonable for so long. If her divinations would be needed, I guess Isida can do something about that.