In the case where the address of a server is not actually resolvable by the address in the Active Directory entry, ie the DNSname field, it is necessary to change the entry, so that PAM uses the address that will be resolvable by DNS.
After importing a Device Group from LDAP you can update the device entry to change the address. Check the Override Address box and then enter the address you wish to use, IP or FQDN. Once the Override Address box is checked, future LDAP refreshes of the Device Group will not change the address.
You can also perform this task using the External API, which will allow for the change to be made on many devices in bulk. Below is the body that was provided to the Put devices.json in the API Documentation under settings.