My apologies, I haven't posted SiteWho in the scripts sections yet, because i wanted to fix all the broken thingies, but it has been dragging on for a while.
In the meantime, i uploaded 1.0.13 on my webspace again, but use it at own risk
Showing or hiding hidden users is done by commandline argument "show_hidden_users" as first parameter. At the moment, i don't see any way to do this without a second sitecommand. I'll might add a feature for your needs in 1.0.14 as well.