Elastic Load Balancer, anyone? I have no sympathy for this company. They deserve to get sued for this. Yes, for something life threatening like this, EC2 is a bad idea, but they didn't even bother to take advantage of the geographic redundancy, much less something so basic as having backup AMIs ready in another AZ in your current region. Of course, a whole lot of companies are learning this now.
As for backing up to multiple regions, I can imagine them thinking that sending everything over the public internet as being a bad idea. However, not having a multi-region/multi-provider failover plan was a worse one.