You do not need a licence to deploy your help OUTPUT at the
client. However you do need a licence if they will use RoboHelp to
access the SOURCE. In summary licences are only required to open
the RoboHelp application not the output produced by it.
Then you are OK. I assume you are delivering Webhelp as this
is the Webhelp forum. If it isn't there may be some issues
regarding others files a user needs installed (which may already be
present and are freely distributable).