Fun!
I couldn’t find a definitive specification for how Roon orders images (but did find many posts going back five years or more with your contributions!). I gather it looks at file names and tries to do something sensible; this correlates with my past observations. This GitHub link is the closest I found…
Unless you have very many problem images (making it worth the investment in time and headscratching) I think I’d delete all images from the folder, clear the cache, then copy corrected and conventionally named images back in.
Hope you find a happy solution!