I had something similar, but instead of symbols and numbers, only certain symbols were used. It was a college handbook for this year’s courses (with teachers’s names, what class, class description, etc.) But certain professors had a footnote and it always had to stay the same. So one on page, it might be the asterisk, dagger, double dagger, etc. But let’s say the guy with the dagger foonote isn’t listed for a class two pages later. Then the page would have asterisk, double dagger. Or on another page, it might be dagger, double dagger (and no asterisk).
My only workaround (which was horrible) was making the callouts white, and typing the symbols and kerning them back over the whited out symbols. I had to do this for the callouts as well as the foonote symbols in the footnotes themselves.
It was a nightmare as the book was pretty big (900 pages). But I think only a few hundred required that kind of tweaking. Then in second pass they started moving things around and footnotes moved and…you guessed it…had to tweak those things again.
I gues we’ll be getting this book every year, so hopefully I can figure something out by next summer. It’s bad enough they give us a half-assed XML file (taken from their website) so actually it’s HTML converted to XML or something. And it’s full of those non-breaking spaces which HTML allows, but not XML. XML deletes those codes. So a bunch of text had no spaces between words.
So I had to open in Text Wrangler and do a ton of search and replaces.
But, I’m going off topic.
I agree with David that it can’t be done automatically with ID’s build-in footnote feature.