Can you convert a PDF to SCORM for free?

Yes. Free converters put the pages inside a SCORM package, which gets the document into your LMS. That usually proves someone opened it or reached the end, not that they understood it.

Does a SCORM file made from a PDF track scores?

Only if the course contains questions. A wrapped PDF has nothing to score, so a score or pass mark needs a course rebuilt with questions in it.

Does Reigniter export SCORM 2004?

No. Reigniter exports SCORM 1.2 only, on the Interactive Training and Agency plans. If your LMS requires SCORM 2004, use a tool that exports it.

How to convert a PDF to SCORM, and when a converter is not enough

a PDF cannot be saved as SCORM directly. Its content has to go into a tool that builds a SCORM package, which is a zip file your LMS can launch and track. A free converter gets the pages into your LMS quickly, but if you need questions, a score or a pass mark, you need an authoring tool or a training platform that rebuilds the PDF as a course.