I think I've got a few more ideas on who possibly voiced who:
Octave (Daimon)- Linda Ballantyne (I feel only she could be able to do the soprano notes)
Ikasaman (Daimon)- Kirsten Bishop?
Upasocon (Daimon)- Loretta Jafelice (Her "The honor is mine, Mimet" line gave it away)
Telulu- Kirsten Bishop (Sounds almost like Kaorinite)
Chad ("Mixed Emotions" episode)- Roland Parliament?http://www.youtube.com/watch?v=EqCelQbRgr8
(Up to 0:06) He doesnt say much, but he does sound like an older, less geeky Melvin.
Mugen Security Guard ("Next In Line")- Tony Daniels (Think Jedite but a slightly deeper voice)
Sergei Asimov- Vince Corazza (The accent is a giveaway)