Apex domains cannot have CNAME records.
Question and response
Question
dig ibmc.cnv-qe.rhood.us. NS
Answer
ibmc.cnv-qe.rhood.us. 5 NS ns-440.awsdns-55.com.
ibmc.cnv-qe.rhood.us. 5 NS ns-1145.awsdns-15.org.
ibmc.cnv-qe.rhood.us. 5 NS ns-783.awsdns-33.net.
ibmc.cnv-qe.rhood.us. 5 NS ns-1815.awsdns-34.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0