The only thing you could do, as far as I'm aware, is have your friend go into Options (Alt+O), IRC and under Show In Active, check Queries. Then all /query and /msg messages will show up in the active window, the window that he/she currently has in focus, rather than having a seperate window pop up.
I'm not sure if querries could be sent to a specific channel through a bit of scripting or not. Maybe one of our scripting wizards can help.
