Sorry, but that would be a direct violation of the license agreement, no?
Why would you want folks to use RoboHelp via a web site?
Or did you mean to say that you wanted to create a RoboHelp output such as WebHelp and use it? If so, that's probably possible, but would require some work. I don't know if Wordpress offers an ability to upload a folder structure.
You can use RH as your source tool and then import the output into Wordpress. Take a look at this link which explains what is involved.