Interesting. Not your average powershell module.. get-help get-ncvol -online would have been more along the powershell rules I did notice another post asking the same question after I posted this. The nchelp cmdlets are not intuitive even for very well versed PS users unless you review every single cmdlet in the module.
Get-Help works just fine without the "-Online" switch. The help isn't plublished to a URL, so there's no place for it to retrieve the information from. As @JGPSHNTAP noted, there's a number of places to view the help:
Get-NcHelp / Get-NaHelp = List the cmdlets available for the respetive platform ("Na" = 7-mode, "Nc" = clustered).
Show-NcHelp / Show-NaHelp = Open the HTML based help in the default browser. This is a convenient way to view the equivalent of "Get-Help $cmdlet -Full" for all of the cmdlets, but in a browser.
And, of course, you can use "Get-Help $cmdlet", with all the normal parameters (Full, Examples, etc...except Online).
Hope that helps.
If this post resolved your issue, please help others by selecting ACCEPT AS SOLUTION or adding a KUDO.