A traceroute seems normal, but it just hangs forever in my browser.
The domain & sub are on different IPs.
http://18.104.22.168 loads and shows the bad_http_conf error--which seems to be normal when accessing a shared IP at DH by the IP.
http://22.214.171.124 hangs the same way your domain does.
Maybe there's some sort of problem with that IP? Did you get a unique IP for your domain? If not, I'd guess that other might be having the same problem if they're on that IP.
In any case, that will probably be a job for support, so I'd submit a ticket explaining everything you said here.
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