First, try finding a .dlg file with KotOR Tool that is spoken by a Trandoshan.
Look at what is used for the VO_ID (under main structure) and the Sound fields (under each EntryList structure). You can copy those values into the same appropriate fields of your new dialog.
If you were doing this with actual spoken words, you would use the VO_Resref fields instead of the Sound fields.
Take a look at this (
http://www.lucasforums.com/showthread.php?s=&threadid=126746) thread for some background on those fields.