BB: I haven't done this repair so this is pure speculation:
In your first picture, there looks to be a spring on the cable assembly (near the motor?). If you compress the spring, does that introduce slack into the cable system?
In your second picture, it looks like the wheel has a broken section of the flange at the 7-8 o'clock position. Did the cable jump the wheel during operation? If yes, that broken flange may be why. It may need to be replaced or this could happen again.