iOS Album not syncing all files

We may be in a unique position, but I wanted to reach out to the community in case anyone has experience with multiple linked albums and Canvases.  We have set up 20 MC327 units for class presentations. We have 20 albums in Apple Photos called A - T. Unique images in the album will sync to the linked screen. Duplicate images (like our instructional slide) only go to the first linked Canvas. We are managing all 20 through the same AppleID and Netgear account.  Multiple devices (MacMini and iPad) result in duplicate linked albums in the Canvas.