"This still seems to be a problem in which the lady opens far too wide."
The lady does not open in an open telemark, period.
Due to the direction of rotation she actually "closes" to promenade position rather than "opening" to it.
To be specific, after her feet stop turning an an alignment consistent with promenade, her body, upper body especially, needs to continue turning anticlockwise so that her body will be closed to her partner in the resulting promenade position rather than opened away from him.