Roon on Desktop says clearly it is by the composer Emil Szymon Mtynarski. This composer is not that well known (to me), so it would be helpfull to see this info while listening to the track.
But when I listen to the track via Roon on Mobile (ARC) I see only the following:
Adding this credit to ARC’s Now Playing screen is something that only Roon Labs can do, so I’ve moved this thread to the Feedback > Feature Suggestions category.
If this feature suggestion is important to you, please vote for it by using the Vote button at the top of the thread. Thank you.
AFAIK is there this longstanding (and so far never fixed) issue that composition credits don’t show for the first part of a multi-part composition in Roon. Maybe its just the same for Roon ARC too? See for example:
PS: If so then it is a bug in ARC too and fixing bugs shouldn’t require a feature suggestion.