Split PDF file with digital signature

@try67 and @Test Screen Name are right of course. Digital signatures contain a cryptographically secured fingerprint of the document (not page!) they refer to, and albeit there are a few changes that are allowed to be applied to a digitally signed PDF as an incremental addition after the original file end, document restructuring is not among them.

But have you made sure you have a single PDF with such a multitude of digital signatures with visualizations spread over all the pages? I wonder because such a construct usually does not make any sense at all.

Thus, have you made sure that you don't merely have some image of a signature stroke on each page and one global digital signature securing the document as a whole? Or alternatively a portfolio PDF containing numerous single page PDFs individually digitally signed?

It is not just impossible to do, it doesn't even make sense. It seems to but here is the problem. THERE IS NO SUCH THING AS A SIGNED PAGE. All signatures are for the whole document. Some people are misled by the signature STAMP - but this means nothing, it was a mistake from Adobe to even put a stamp there. This leads to the terrible, terrible mistake of "signing every page" to match some paper workflow. This is completely wrong and will cause enormous problems; the workflow needs to be designed in full knowledge of how digital signatures work.

Not possible. A digital signature can't be extracted or moved from one file to another.