Developer Build Icon not showing in Apple Fitness

I am building an app that sends workout data to Apple Fitness. During development I noticed that my App Icon does not show up in Apple Fitness and it's just a blank space. The Icon seems to show just fine in Apple Health but not in Apple Fitness.

I did the same test with the production version of my app and I can see the production icon just fine in Apple Fitness. I am trying to find information about which app Apple Fitness uses since it seems to differ from the one Apple Health uses. ChatGPT seems to think that Apple Fitness uses the App Store Connect icon (which I have for my prod app but not my dev app), but I cannot seem to verify that assumption with any kind of documentation.

Can I please get information about which icon specifically Apple Fitness uses when displaying third party app integration information?

Developer Build Icon not showing in Apple Fitness
 
 
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