i think it would be technically possible to somewhat automate the search for mismatches by scraping / parsing the HTML in the taxon’s taxon scheme page (ex. https://www.inaturalist.org/taxa/326191/schemes) and then seeing if the GBIF taxon has the same name (ex. https://api.gbif.org/v1/species/9734350). that said, you would have to do this one taxon at a time, and it would not be a super efficient process.
if someone had access to the iNat database, or if iNat staff included GBIF ID in their taxon exports or taxon API, then you could get GBIF IDs for all taxa at the same time (or at least in chunks), but then you would still have to look things up over at GBIF, and you’d still have to do that in chunks, as far as i’m aware. so still not a super efficient process.
now for some speculation… i’m not familiar with the process for creating new species, but i wonder if it involves using the parent (genus) as the template for the new species? if so, that might explain how the genus-level GBIF ID might end up on multiple species, and in such a case, i guess you would just want to either procedurally or technologically prevent the GBIF ID from getting copied from another taxon.
not sure if there’s really still a bug here though. seems like a data problem (which for the original reported problem has already been fixed), and even if the source of the bad data could be prevented with a code change, that might be more of a feature request than a bug fix.