Sharon Kinne was blonde, four inches taller than IW, had a "red port wine" scar on the left side of her face, and a skin pigmentation disease. IW was described being very attractive, and maybe it's just me, but Kinne was gawky-looking. I don't see anything but the faintest resemblance. Also, I don't think she'd be able to learn how hide her American accent in that short of time, in addition to learning all those languages. If there's one accent that Europeans would recognize, I would think it'd be an American one. Add to that what Melmoth and Kemo said, and I do not think Kinne is at all viable.
Mildred Batoche looks more like IW, but in additon to the tattoo, she was also much younger. There doesn't seem to be any other information on her, so it's hard to judge.