Does the "DNSBackward" field get populated whether a ping comes back or not (i'm betting not based on my system)?
I'd like to add this as a feature request.
I don't know the mechanism used to populated that field, but the DNS entries are there.
On the DMZs of our firewalls where IPs are NAT'ed, the firewall will not respond to ping (hairpinning). IPAM shows the IP as used (neighbor scanning) which is designed to work past this, but DNS/Hostname is not apparently populated.
a ping -a <ip address> provides the entry needed.