Commons page names can be found via Wikidata: -> linked Wikidata item -> Commons gallery (P935) and Commons category (P373)
(Categories and gallery pages are competing paradigms for organizing images on Commons; a topic might have one or the other or both. The names might or might not match the English Wikipedia article name; there is no effort to ensure they would.)

DBPedia gets most of its data by parsing Wikipedia pages, so the names match most of the time. I'm not sure how they handle Wikipedia article renames, though.