for what it’s worth, i made something the other day that could probably be used in this particular case. see https://forum.inaturalist.org/t/provide-a-way-to-filter-observations-by-disputed-ids/6698/15.
it was written to find observations with identification disagreements, but the workflow – finding identifications that meet certain criteria and then getting the associated observations – can be applied to this, too. (just filter for identifications of a specific taxon by a specific user, instead of looking for identifications with disagreements.)