In the game Wiki, there is a place where you can put in the people allowed to edit the wiki page, separated by semicolons.

I did this using the character names, but it does not seem to work.  What name do you put in there to allow them to edit?  Is it their RPoL name in the RTJ or something besides the character name?

RPOL name - not game name.

Doesn't this then disclose the RPoL name of the individuals for everyone to see?

Yes.  By default, if you leave it blank every member of the game can edit it, and the names won't be listed. But I believe if they do edit it, then the edit history will reveal the username.