iPadOS and Using Thumb Drive, folder.jpg Not Being Used as Folder Artwork

I have lots of kids’ movies on a thumb drive for travel and use it with an iPad. Each movie has its own folder and each folder contains the movie and two images - one named folder.jpg and one with the same name as the movie file. When I Add Files, Infuse continues to show folder icons instead of the artwork from folder.jpg.

Am I missing something here? I thought the folder.jpg images would be used as the folder artwork.