Originally posted by S_W_LeGenD
UnuThul issued a (telepathic) call across the galaxy that a large number of Jedi felt and found enticing. However, many were able to resist his call.Jacen Solo was not able to resist the call initially but he managed to develop a countermeasure against it at a later stage. UnuThul eventually realized at some point that Jacen had become immune to his telepathic abilities.
Because that call was much like what Kaan, Luke or Krayt did. It's not a direct mental domination. The fact that they found it enticing regardless just proves even passively Unu'Thul is a telepathic powerhouse.
When 'Thul sets his sights on someone, even Luke isn't completely safe. So breaking the Outlander really doesn't compare to almost breaking Skywalker.