Metadata Agent Secondary Provider / fallback not working

When configuring an agent in Plex settings, it says you should be able to list secondary providers as fallbacks, so that if provider A doesn’t have a field, provider B will fill it in (if available). This does not seem to be working with custom agents as the primary provider, as shown below where the plex TMDB example provider is primary, and the Plex series provider is secondary:

When using the example TMDB provider OOTB by itself, it is not currently built to pull in, for example, audienceRating. Plex Series does pull in audienceRating (from TMDB) successfully on its own, when used as the provider with no customization. But, when Plex Series is the secondary provider, audienceRating is not filled in for series. I’ve tested with another custom agent based on the TMDB example, same behavior is present.

  1. Is this an issue with the custom agent being the primary?
  2. Or am I misunderstanding about how the behavior should work?

Server: Version 1.43.0.10467

Updated to 1.43.0.10492, issue unresolved

This is a known issue with these specific fields when using the Plex provider with other providers.

This is something that is on the list but not currently a high priority so cannot give an eta on when it will be addressed.