Its not just SoW - all the standard buffs check for attack and active skills, and voodoo doll has neither. If you add a couple LS to the deck, the AI will (in theory) use those on the dolls, then buff the dolls (cause now they have vampire).
Of course, the AI will probably stack all the buffs on one doll, so I don't see what good the fractal is doing. If you were using SoP, then having lots of dolls would help, but they would get attack from the SoP and you wouldn't be seeing this problem.