ApplePay integration with multiple providers

We have a checkout page on which clients can configure the providers we've integrated with for each currency.

One such provider is Stripe, with which we have already integrated ApplePay and host a merchant domain association file.

Now, we're getting requests to support ApplePay with other providers.

The issue is that we can't tell Apple to use a different path to domain association file for domain verification.

And, replacing the existing domain association file seems like a hack, since I believe it's needed for domain re-verification.

We're thinking of using subdomains for serving the domain association files for different providers.

But, we have some questions on how ApplePay domain verification works to understand how we can solve our problem.

Firstly, can we use subdomains for individual domain verification? If we already have example.com verified with Stripe, can we serve the domain association file for the other provider with provider.example.com and have the verification work?

Secondly, let's say our domain is example.com, and we can use provider.example.com to serve the domain association file and verify the domain. Then on example.com/checkout, will using an iframe with provider.example.com/applepay to host the ApplePay button work?

This thread suggests otherwise, but we want to confirm.

Lastly, is the only way to make an ApplePay payment for provider.example.com to use that subdomain? So redirecting to provider.example.com/applepay would work?

Thanks for your help!

ApplePay integration with multiple providers
 
 
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