Flatten Transparency is Ruining my Lines! Please Help!

If you view the PDF in Adobe Reader or Adobe Acrobat DC you can right-click in a blank area of the document and choose "Document Properties" in the flyout menu. There will be a tab for "Fonts". That will provide a list of all the fonts in the document and the type of fonts used.

Generally speaking, PDF files are just not edit-friendly. Adobe Illustrator is an exception, but only because it can create PDF files that include Illustrator data.

PDF files made by most other applications (even Adobe apps such as InDesign) are meant strictly for document viewing and printing, not further editing. All sorts of seemingly odd things are done to the type and graphics objects in the document to make the PDF's content appear accurately and print accurately on different computer systems and different computing platforms. The exported PDF file may contain a rat's nest of clipping masks, clipping groups and all sorts of other junk in order to do that. Worse yet, if the PDF was created to optimize file size then all sorts of objects may be changed. Paths get broken open. Some letters in outlined text get turned into line strokes. Much of the time the Flatten Transparency trick is the only alternative. At least Illustrator can do that. Rival vector drawing applications are in even worse shape at importing PDF content.

If you're having to make edits to a document created in MS Word or Finale it would be far easier to just work with a copy of the original document rather than have to re-build it from a de-constructed PDF.

Third party plugins, such as Vector First Aid from Astute Graphics, can help solve a lot of problems when someone has to work with a customer provided PDF file. But the plugin can do only so much. Even with the aid of that plugin it might still kill a lot of time re-building content from a PDF into a clean, editable document.