just edit for the groups if needed, if you edit the server names, by experience it will not work.
For the test, please try the Sylink Replacer Tool, it is better to receive the Tool from Symantec Support that's why I suggest you to create a case for it.
They can also give suggestions with your situation.
The tool is recommended for big clients (ex, 200+ clients) instead of reinstalling them 1 by 1 then reinstall, the tool is used.