Replaced the part! It took under 15 min.
Unplug dryer. Remove the two screws on the cover, and that one holds the timer in place. Rotate the timer out and remove the wires (one at a time, so you know which one goes where) from the old timer (use pliers to get a grip) and place it on the new. They are slide fit so very easy.
Put everything back and now we have a functioning knob again!