Yelling at him definitely doesn't work. My greyhound had S.A when I first got her but crating her helped IMMENSELY and she never tried to get out of it or destroy it. I came home from work one nite and she had ripped the trim off the bathroom door and pulled the controllers off the heater. I couldn't yell at her b/c I was too shocked. I was speechless.
But Yelling at him just gives him negative attention and besides that they have no sense of time and what he did was hours earlier and yelling at him - he has no clue why.
I would try to get the Comfort Zone plug in's - that might help.
I'd be very careful with a muzzle b/c if he gets his paw or nail or something stuck in it you might come home to a bigger mess and a more panicked dog.
I'd say if all else fails - try contacting Nancy to talk to him.