It looks like it might, Peter. This statement in particular looks promising: "Ability to include a search on an intranet or other information sources outside the project".
Now I just need to figure out the other end -- searching a Confluence site using this tool. I have a feeling it might not be all that straightforward. Hopefully either the ZoomSearch documentation or the Confluence documentation will help.
Looks like I got the answer to my question on the ZoomHelp user forum, Peter. Probably won't work without "a fair amount of custom development." Oh, well.
In Ray's response he says "One which happens to be hosted locally on the hard disk, and another which is served over the web". The webhelp is not being hosted locally so it might be worth pointing that out. If both information sources will be on the same server you should state that too.
Another option is to have a ZoomSearch setup as in the demos on my site where the user can choose which search to use. One button would bring up a ZoomSearch search of the help and another button the search of Confluence.
See www.grainge.org for RoboHelp and Authoring tips
Ray's assessment is accurate ... my WebHelp system actually does install on the user's hard drive, and the Confluence site is on the Web.
Your other suggestion could work, but I think for the time being I'll just go with my current solution, which is to include a link to the online knowledgebase both in the TOC and the welcome page. I'll take another look at your samples, though. Thanks!