No defrost heater test good bi metal therm is good is there a heater control board on this model?

Refrigerator & Freezer Repair
1

Brand:kenmore
Model Number:59676574600
Main Symptom:no defrost
What happens & when:back panel frozen

Error Code (if any):
Parts or tests already tried:bi metal sensor tests good heater test good
Photos / video link:

2

With the heater being good, the electronic control located in the top of the console would be next. WPW10207861 Electronic Control Board | Genuine Whirlpool OEM In Stock, it is showing NLA. You may find one on E-Bay or somewhere else on line.