ns03.dominos.com has no MX records.
Question and response
Question
dig ns03.dominos.com. MX
Answer
The response has no answer records.
Authority
dominos.com. 900 SOA a1-66.akam.net. dns-admin.dominos.com. 2026022602 10800 3600 604800 900
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0