iNat does provide a periodic export of its taxonomy as part of the DWCA files it generates to transfer data to other systems. that includes common names, and contributor, although i believe the contributor noted would be the person who made the latest update, not necessarily the person who added the record, and i think the contributor sometimes gets left blank in cases where names are bulk uploaded or maybe also if the names were created long ago.
you can find some more information here: https://forum.inaturalist.org/t/using-sql-to-query-inats-dwca-taxonomy-export/29377.