mx.iiwf.info has no CNAME records.
Question and response
Question
dig mx.iiwf.info. NS
Answer
The response has no answer records.
Authority
iiwf.info. 3195 SOA dns.iiwf.info. hostmaster.iiwf.info. 1741292596 43200 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0