Calibre and online sites can convert from PDF to Epub usually lose most of the format. I tried PDFElements, with similarly poor results.
Is there any service/app that actually works and converts a PDF to Epub in a way that resembles closely the original?
You can have fixed content as well, but it needs to be flagged in the document- for example, for illustrated books, or cover, title, and cpr pages.
Op needs to talk with whoever is doing the conversion and tell them what they want. But it’ll probably drive the cost way up- especially if it was automated (and it probably was/is)