Hello Sebastian! Thank you so much for the reply, it's nice to know the reason why/how these things work. Your explanation makes a lot of sense, and as a fan who would enjoy these custom graphics, revisiting this "Championship" issue in FHM11 would be great - if you see a better way to handle it of course!
For now I can use the fix method you suggested to get around it!
I wanted to provide a little extra information as you mentioned that All-Star Games are not league specific as I was able to get a custom All-Star Award icon working with the "national_hockey_league_award" prefix.
(I've attached an image below)
If this isn't intentional - please keep it, it's nice to have more customization options.