Can't conceive how a wind turbine could confuse TCAS, especially if you were getting altitude signals. As I understand it, TCAS derives altitude data cooperatively, from the target's transponder. It's not a radar in the traditional, military sense. So you shouldn't be getting false returns off the turbine blades (or anything else, for that matter).
The only thing that even vaguely works is that the blades are somehow reflecting valid TCAS responses from other traffic, so that you get a valid altitude but an invalid direction. Sounds a bit unlikely though.