Universal Links not working with subdomains without AASA on root domain

Hi all, I'm trying to set up universal links for my app but it's not working.

What I want:

cogover.com → Safari (website) - NOT my app

*.cogover.com (any subdomain like abc.cogover.com) → My app

What I did:

Added applinks:*.cogover.com in Xcode

Put AASA files on all subdomains

They work fine (checked with curl)

Problem: All links still open in Safari, not my app. I do not put AASA on my root domain cogover.com because I don't want open my app with root domain.

I have checked TN3155: Debugging universal links | Apple Developer Documentation but it only say about universal link works with both root domain and subdomains.

Weird thing I found:

I checked how Salesforce does it - their *.force.com subdomains work perfectly. But when I tried to check their setup, (https://force.com/.well-known/apple-app-site-association) doesn't seem to exist either! So how does theirs work?

Even stranger - Apple's CDN has their file cached at (https://app-site-association.cdn-apple.com/a/v1/force.com) but the actual domain doesn't serve it. Can Apple's CDN have a file cached even if it's not on the website anymore?

Thanks for any help!

Universal Links not working with subdomains without AASA on root domain
 
 
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