What Talisman expansions give a PvE end goal?
I am going to assume that you only are considering the Fourth Edition Expansions by Fantasy Flight Games, since I assume that the Games Workshop editions are incompatible. The Dragon and Sacred Pool Expansion should fit your needs with all 3 alternate endings being PvE.


Talisman: The Reaper Expansion (2008): No alternate endings.
Talisman: The Dungeon Expansion (2009): No alternate endings.
Talisman: The Frostmarch Expansion (2009): Crown and Sceptre, Ice Queen and Warlock Quests
Talisman: The Highland Expansion (2010): Battle Royale, The Eagle King, and Hand of Doom. 
Talisman: The Sacred Pool Expansion (2010): Demon Lord, Judgement Day, and Sacred Pool
Talisman: The Dragon Expansion (2011): Dragon Slayers, Dragon King, and Domain of Dragons
Talisman: The Blood Moon Expansion (2012): Horrible Black Hole, Lightbearers, and Blood Moon Werewolf.
Talisman: The City Expansion (2013): Merchant's Guild, ??? (not released)