Hi Jurassic - your suggestion worked. Now I see the following which I presume is correct for such an action? I've replaced my tld domain with "tld".
[
[email protected] scripts]# ./cpdig tld.com A --verbose
[1611603783] libunbound[9513:0] notice: init module 0: validator
[1611603783] libunbound[9513:0] notice: init module 1: iterator
[1611603783] libunbound[9513:0] info: resolving tld.com. A IN
[1611603783] libunbound[9513:0] info: priming . IN NS
[1611603783] libunbound[9513:0] info: response for . NS IN
[1611603783] libunbound[9513:0] info: reply from <.> 192.33.4.12#53
[1611603783] libunbound[9513:0] info: query response was ANSWER
[1611603783] libunbound[9513:0] info: response for . NS IN
[1611603783] libunbound[9513:0] info: reply from <.> 199.7.83.42#53
[1611603783] libunbound[9513:0] info: query response was ANSWER
[1611603783] libunbound[9513:0] info: priming successful for . NS IN
[1611603783] libunbound[9513:0] info: response for tld.com. A IN
[1611603783] libunbound[9513:0] info: reply from <.> 192.203.230.10#53
[1611603783] libunbound[9513:0] info: query response was REFERRAL
[1611603783] libunbound[9513:0] info: response for tld.com. A IN
[1611603783] libunbound[9513:0] info: reply from <com.> 192.33.14.30#53
[1611603783] libunbound[9513:0] info: query response was REFERRAL
[1611603783] libunbound[9513:0] info: resolving ns2.tld.com. AAAA IN
[1611603783] libunbound[9513:0] info: resolving ns1.tld.com. AAAA IN
[1611603783] libunbound[9513:0] info: response for tld.com. A IN
[1611603783] libunbound[9513:0] info: reply from <tld.com.> 55.xx.xxx.xxx#53
[1611603783] libunbound[9513:0] info: query response was ANSWER
[1611603783] libunbound[9513:0] info: response for ns2.tld.com. AAAA IN
[1611603783] libunbound[9513:0] info: reply from <tld.com.> 55.xx.xxx.xxx#53
[1611603783] libunbound[9513:0] info: query response was ANSWER
[1611603783] libunbound[9513:0] info: response for ns1.tld.com. AAAA IN
[1611603783] libunbound[9513:0] info: reply from <tld.com.> 55.xx.xxx.xxx#53
[1611603783] libunbound[9513:0] info: query response was ANSWER