OK, now, we may have to become a bit more creative. I have an idea, however, it may or may not work, and it is a little bit messy. And it depends a lot on the document and the way the already created named destinations are created and named.
Assuming that the references are kind of consistent, we may use the Redaction tool to find all the occurrences of the source points. As the Redact markers are annotations, we can convert them into links (which are also annotations). If we have a kind of logical connection between the text found and the named destination, we could even semi-automate this.
It is possible to do something like that (I have a project where we are doing something similar, and the client is very happy (tm) with it. Describing the solution would, however get beyond the scope of this forum. So, if you consider "buy" as an alternative to "make", it may be a good idea to talk in private; feel free to contact me at max at prodok dot com.
Max Wyss.