Testing AppClip using TestFlight

I have the local AppClip testing working - but some would like to test using TestFlight. Does the server https hosting the JSON file need to match the associated domain URL in the AppClip? I am currently looking for free https hosting for the apple-app-site-association file and wonder if the location of the file needs to match the associated domain or not.

Testing AppClip using TestFlight
 
 
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