Destroying one AZ in one region would not (should not?) take down a single AWS customer. ALB are multi AZ, it's trivial to deploy services across azs. Everyone should be ok.
Although I'm sure AWS has not done a disaster test where they actually bring one down so who knows if regional services would come out unscathed.
How pissed off do you think he's going to be when he learns that not only was the bomb fake, even if he had a bomb it would have amounted to little more than a disaster recovery test?