Well it would make sense that perhaps Revan didn,t wish to just anhilliate his own forces right away whenever he did find the true sith.Think about it.Revan was a cunning warrior and strategist when it came to the Mandalorian wars.Although some of his men died he outsmarted the Mandalorians.Thats no ordinary feat.Perhaps before he decides to gather his forces,he wishes to learn more about the new threat which cannot be denied as it does exist.Although even if he does get as far as eliminating some of the true sith there will be some left over.Thats why there is the new sith war that occurs some 2000 years later.But nevertheless it cant be that nothing just happens because by the way Kotor 2 ended.It is inevitable.I mean one more thing is how can anyone be redeemed and not be redeemed at the same time?Either you are or you aren,t.This was proven through out the whole story of Anakin Skywalker through all the episodes.He was evil then changed to good at the end.But there is only one path or the other that can be chosen.There really isn,t a in between.Even for Darth Kreia.She was still ultimately a sith lord.Thus hence the title name Kotor 2 The Sith Lords.That is all.