In the Devastation: Summons.
In Sverag, Stronghold of Rage: Summons.
In Razorthorn, Tower of Sullon Zek: (no data)
In Sarith, City of Tides (non-instanced): Elite soldiers are spawned by Tactician Perak.
In Grelleth's Palace (non-instanced): These spawns in and behind the throne room area.
In Grelleth's Palace (instanced): Part of the group mission "The Queen's Decree" (see this quest entry for details) and the raid expedition "Grelleth, Her Majesty the Queen" (see this quest entry for details).