Help with summary!!!

[EuGig]

Hello everyone!!
I'm using the library for work, in the following way:
Different processes create different documents. The first process creates a summary.
A the end, I merge all the documents and I would like to update the summary post-merge with all the new titles and pages.

As far as I know, there is no such functionality in the API.
I also tried to go through the merged document and to search for titles and corresponding pages, but I cannot get the page number (I cannot a function that does that).
Any suggestions? Any help? Thank you!!!

(Putting in macros does not help, because the final output is a .pdf file.)