I don't like blood bending much and that would be the girl, Xana's department anyway.

I think Asami would be open to tapping into her fire element, intrigued but still unsure about adding water, and come wind, she'd get it but then realize it was wrong and back out/tell the others about Xano and Xana. That was the plan right? I assume they wanted Asami to be their weapon but if not that, a way to ensure that they could put the elements in themselves if needed. Since Xano is power hungry, I assume he'd be the endgame villain in this arc anyway with all four elements.