mx2.akamai.com has no CNAME records.
Question and response
Question
dig mx2.akamai.com. NS
Answer
The response has no answer records.
Authority
akamai.com. 300 SOA ns1-2.akam.net. hostmaster.akamai.com. 2026022503 7200 3600 1209600 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0