The map's makers are named by the story

The Marauder's Map arrives as a joke and a tool. Its makers sign themselves with nicknames. Later the novels attach those names to a group of students from the previous generation, the same circle tied to an animagus secret and a betrayal.

Once that connection is on the page, fan essays that treat the signature as unsolved are replaying a first reading. That replay is a pleasure. It is not a research gap.

Spoilers live in this note on purpose. The Stacks entry on the map stays vaguer.

Naming the makers does not exhaust the map. How much of the castle it refuses to show, and why a student object knows more than the staff, is still a live design question.