Act FOUR? I know who the surprise help is, from looking at the wiki (God bless Game Widow), and I can't imagine what would happen during the Lakeside interlude that would be connected. If you're thinking about choosing the Neutral/Order/Scoia'tael path, that would mean that if you choose the wrong path AND kill both "monsters," that would leave you with no one, and it seems like SOMEbody is supposed to turn up at that point in the Epilogue.