[tcoradeschi]

Short answer (long one, too) is: take it apart. I suspect that once you pull off the rotor, you will know what is wrong.

There is a funky hinged piece which goes on the end of the cable - it cams out to spread the shoes when you engage the brake. Maybe that has come apart?

The guts of the parking brake is a bit of a wrestling match to R&R. I’d almost forgotten how much I detested drum brakes, back in the day, until I redid the shoes and the replaced the piece noted above.