actually no. its kinda like the trailers. kinda like when they have bastila on the unknown planet which is impossible. or hk-47 on taris. they were just teasers
its not imposibale fo HK-47 to be on taris. if you are playing the pc version you can enter cheats that will transport you to any of the planets you want. it also lets you level up. if you use to "warp" cheat and heve HK-47 and bastila or anyone else in your party you want you can take them with you to wherever you want to.
you can get HK on taris, and you can do alot more, all you need to do is unlock the travel droid
-kill juhani -dont go to kashak -before you are about to go onto the liviathan pick dantoine as destination -right after you get back onto the Ebon Hawk DO NOT ask HK what he thinks about you bein Revan
after that in the cocpit of the ship there with be a Galixe travel droid that can take you back to the endar spire or even to taris, unkown planet... ext.
(if you get off the ship the droid will dissappear)
