What I did was open the archive and filter for 'Ask', then use crtl-f. Still a tedious process because it only searches a part of the page, I guess it does not load the whole thing at once?
Here is what I found:
Jadis is never wrong,
because Jadis is the Bearer of the Shape.
Jadis' knowledge is unrivaled.
Jadis is (or rather was) very powerful.
The technopriests died when beholding the Shape.
I found nothing which directly says she has pefect knowledge of the future, just that she is never wrong. Note that all her prophecies are also filtered through the interpretations of her priests.