The 'cm' is your Avaya CM? We're in the NonStop and Distributed Systems forum. I'm guessing it landed in the wrong forum.
The expand fails with "time offset is invalid" error in the Prognosis Web UI in the Administration view? That'll prevent you make any changes like you've described.
Try this - on that monitoring node server file system try rename the ircfg-nodename.xml file (where nodename is the name of that monitoring node ), in the Prognosis\WebUI\IIS\Administration\Config folder. Then Log out and log back in into the Administration page and attempt to expand it again. If this works then it should rediscover and list. It might take a minute. If that fails, make sure to request Support - describe what you've already tried and include screenshots and irfax for a more in depth investigation.