Mode selector switch to change airflow from floor to defrost is stuck on defrost

I removed the front bezel and discovered the mode selector cable was bent (likely from trying to force it), which I was able to straighten. But trying to move the cable itself back and forth did nothing. The cable is stuck in one position. There is a little free play, about a sixteenth of an inch, but not enough to open/close the door controlling airflow.
Is it possible to get to the other end of the mode selector cable or is this accessible only by disassembling the entire dash?