The paymentstestX.wmcloud.org domains are periodically crawled by Apple and Amazon to ensure that they are still valid. If that happens when we don't have the ports forwarded to a development machine, the crawl fails and we get alarming emails.
Apple requests /.well-known/apple-developer-merchantid-domain-association.txt
Figure out which path Amazon requests, and set up an nginx site (we've already added the nginx puppet role) to serve those files and proxy all other requests to the forwarded ports.