There's no cover art presence icons shown for any RGs in https://musicbrainz.org/search?query=arvo+part&type=release_group&limit=25&method=indexed&page=1

Compare with direct search at https://musicbrainz.org/search?query=arvo+part&type=release_group&limit=25&method=direct which correctly shows most of these RGs actually have cover art.

We probably need to load the data from the DB when massaging the search results, since I expect this data is not indexed by the search server at the RG level.