It’s listed as a synonym on POWO, there are no controversial comments/IDs, no one has flagged it to request a deviation. External sources like EOL and COL don’t picture into the taxonomic authorities that iNat references for taxon changes/curating. So unless you have reason to consider a deviation from POWO, I would just go ahead with aligning with POWO. I inactivated it.
Re taxon swaps vs. inactivating taxa with zero IDs:
Yeah, for these taxa with no IDs or other associated info, I tend to just inactivate them. Aside from any common names being transferred during a taxon swap, it also
- takes longer,
- transfers conservation statuses (which might do more harm than good),
- adds a usually pretty useless dashboard notification to anyone who’s made IDs of the output taxon or is subscribed to the taxon for another reason (e.g. it is on one of their personal lists), and
- the curator guide also says atlases and range maps get transferred, but I honestly haven’t delved into the particulars of that. That seems like asking for problems in any but the simplest of cases.
A taxon swap should probably specifically ask “Do you want to transfer the following items to the output taxon? 
Vernacular names Range map Atlas Conservation Statuses” etc
Yes, I do a specific search when I choose to inactivate rather than do a taxon change: https://www.inaturalist.org/identifications?taxon_id=556178¤t=any