...to create a gateway to an IM provider from LibraryH3lp, you first have to create an IM account in that provider, under the name you want shown. Otherwise there's nothing to link up to.
I realize that that should be fairly obvious, but since we don't already have IM chat, I didn't think about that. So, with this major breakthrough, I'm going to call it a day in the virtual reference world. Tomorrow I will be back to learn enough to make it a comprehensible explanation for my fellow reference librarians.