Just noticed this, I imported a Female Drider model to my map and have only replaced the model of the Nerubian Queen, The Unit Sound Set, is still "Nerubian" But when she dies it sounds like a night elf archer dying or some female scream, its certainly not the loud n cool nerubian death sound...
Event objects. Load your model in Magos' Editor, open Node Manager, scroll down to the little camera icons with strange names, and open them up until you find the desired sound, and change it. Oh, you cna also change spawnobjects such as footsteps and blood too.
Yeah they are events, there is a list of all those events (some are missing, like the death sound of the spell breaker and the sounds of the patch) in the "Art Tools Documentation.pdf" that comes with the art tools