It sounds like the tech that went in your home went above and beyond going against rules and risked his own health and possiby even death to fix your cable box which you stated worked once he was done. I say it's a bit your own fault considering no one is able to go into your home and you didnt check other tv's to be sure there werent any issues elsewhere in your home. I dont blame Cox technicians for being safe and not enterning.
At the same time it seems a bit odd that every box you touch seems to not work... just sayin...
Basically, I wouldnt give them a hard time for wamting to keep ppl safe. You should also always have a backup plain