relay-se.imr.shell.com has no CNAME records.
Question and response
Question
dig relay-se.imr.shell.com. NS
Answer
The response has no answer records.
Authority
shell.com. 581 SOA dns1.shell.com. dns.shell.com. 2831988 10800 1080 2419200 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0