Our closer has zero customer service skills and is not cut out for this company. If you fail multiple secret shops in a row because you can not say "Hi or Hello" to people you should not be in customer service roles. You're one shop away from termination and that's well your own fault. If you can not take criticism and actually do the customer service part of the job -- that's your damn fault! You're a grown adult. 

He's afraid of termination now and has started to weekly call out on secret shop days. Good lord it isn't impossible to say "Hi or Hello" to customers. You're a grown adult if you can't figure it out after repeated fails and management coaching's then you should not be in customer service. 

This is a two sided job: stocking and customer service. Not just stocking. Oh, you can only call out so many times each week before management gets on your rear about it.