I stumbled on this post while troubleshooting an error with Portal. The Organization->Members-> "Add Member" dialog window fails to load, just showing an empty screen. This prevents you from manually adding new users to Portal. The only error in the Portal logs was the same the OP described "failed to validate license counts". The environment also matched the OP - 10.7.1, Highly Available Portal configuration, etc.
The recommended fix of Stopping the Standby server, Restarting the Primary, and then Starting the Standby server does eliminate the license errors and fix the issue with "Add Member" window showing a blank screen. So, this issue does have an impact beyond just cluttering the log. If the Portal is having issues reading the license information, it makes sense that there would be issue with adding new members.
Glad to hear this has been identified and fixed in 10.8.