How would Massassi warriors fare against Kaan's army?
That's a good question. I think they would do pretty good, but Kaan's army has the advantage until they get close. We've seen the Massassi do some damage against the Jedi Order.
Overall, I think Naga Sadow's illusions will win this one. They may be illusions, but they cause actual damage against their foes. And Naga Sadow can create a limitless supply of them. The only way Kaan can beat Sadow's illusions is if he attacks Sadow himself. In this scenario, Sadow's location would be known only to himself since Gav Daragon is not in the picture.